Arbitrary Headcount Limit

""No no no, you don't understand. You see, I only had one ring left to protect my teammates from being in the Edge, so I had to leave the rest behind. I mean, what kind of idiot goes into battle with half his team behind? How stupid would you have to-... R-Rolf, why are you beating your head against the wall like that?""

- Chaz, Conversations Within Elsydeon

Trope common in Real Time Strategy games, in which the overall number of units or the count of a particular powerful, but not unique unit are limited by assigning a completely arbitrary Cap to them. This limit is often far lower than what the resources available or the technical limits of the game engine could allow. Particularly ridiculous when the rule can be broken through scenario design or using a perfectly legitimate game feature. Most often implemented as a way to enforce game balance. It can also be a matter of resources; each unit requires not just rendering power but AI, collision, and other intangibles. This can be partially justified by representing the High Command's reluctance to commit too many resources into one battle when you- in theory- have more than enough resources, though this justification does not work as well when you are fighting THE climatic battle and yet there are only so many units you can deploy.

However, occasionally it may be hardware related, since processing and showing many units at once can slow a game down considerably to the point where it runs really choppy, particularly on high graphic settings, hence the need to limit how many units one can have at any given time. Since developers have to take console hardware limitations into account, or multiple PC configurations, they will usually try to balance between gameplay, and allowing the game to still run smoothly.

Many Role Playing Games have this as well, centered around the three-to-five-person size of the active party. In addition to the Hand Wave explanations common in Real Time Strategy games, Role Playing Games can use the plot to explain the size limit. For example, in Final Fantasy IV, every time it looks like the party will grow beyond five, one of your current members will discover pressing business elsewhere. Or die. Or reveal that they had been This version has something of a real world justification: many groups would keep a reserve behind to prevent the entire unit from being wiped out in one fell swoop.

Recently, the trend of allowing the side characters to "switch out" with the main team is growing, at least in the aforementioned Role Playing Games. If the characters "on the bench" travel along with the main characters but refuse to switch out, or jump in if the active party gets defeated, they're Lazy Backup. (The Gameplay and Story Segregation may also explain that all of them are fighting, and the battle scene simply represents it.)

See also Cap and You Require More Vespene Gas. Kind of related to Conservation of Ninjitsu and Construct Additional Pylons. When applied to temporary things like active bullets, it's One Bullet At a Time.

Adventure Games

 * Maniac Mansion is perhaps the only example in this genre. Dave has six friends who he can ask to help him rescue Sandy. He can only bring two no matter how motivated the other four seem.

Fighting Games

 * Until the Dreamcast came out, most console wrestling games only ever allowed 4 wrestlers in the ring at the same time, regardless of the match type. This included Royal Rumble matches, where you would fight through 29 other wrestlers but only 3 at a time.
 * The WWE Day of Reckoning games for the Nintendo GameCube also had this limit.

Platform Games

 * The enemies in Yoshi's Island are subject to this when spawned by pipes or other similar sources. Oddly, the limit depends on Yoshi - specifically, the number of eggs he has. If the pipe/whatever plus the number of eggs Yoshi has number six or more, it will stop spawning monsters. The real reason, of course, is because these spawn points really only exist to help Yoshi fill up on ammo.
 * Lost Vikings 2 has five playable characters. However, only 3 are present per level. It is Lampshaded throughout the game.

RPG -- Eastern
"Stone Dragon: Blarg! I'm a dragon. Stone Dragons: Or twelve!
 * Hand Waved in Chrono Trigger: When you gain a fourth party member (the maximum number of people allowed in your party are three), one of them has to stay behind to hold open a door, later on, when you're all together and travel through a time gate you end up at . There you learn that no more than three people can travel to an era without getting redirected, so the remaining party members have to stay while the others are adventuring. However, you can switch them at will, and anytime you go to the, you can find them standing there.
 * The Final Fantasy series is a repeated offender:
 * The early Final Fantasy games have very obvious caps on the enemies you can face at once. Nine in Final Fantasy I (arranged into a square, even), eight in Final Fantasy II, and - in the DS remake - three in Final Fantasy III (except for that one time with the frogs).

Red Mage: Impossible! Only a maximum of nine enemies may be onscreen!

Stone Dragons: Fuck you."

"Gnome: You guys play dirty. Four against one? Well, did it by himself!
 * Final Fantasy IV as stated above is a prime example of RPGs that explain the party size limit with plot. However, the GBA remake brings just about anyone back to the party before the final dungeon (and the added bonus content), allowing the player to pick his favorites like in most of the later games. There is no real explaination as to why they can't just all go and bash the Big Bad in the head with superior numbers, though...
 * It does, however, have the most party members available in battle of he main series, with five. The other games have four, or only three.
 * Final Fantasy IV: The After Years takes this one step further in chapter 10 (or the first part of the final chapter on the Wii): Assuming you played all the previous chapters and kept all characters susceptible to a Final Death alive, you will start the chapter with ten characters. As you complete mandatory quests, six more will join you on your airship (again, assuming you played all the previous chapters). However, the game will not let you swap characters (yet) at all: your team is Rydia, Edge, Luca, and the Man in Black, which isn't even a full five characters, with no explanation given as to why you can't at least pick someone on your airship to fill that empty fifth spot. Later on, you get to pick your team of five (out of twenty-two), which is more standard.
 * In Final Fantasy VI, when the party is attempting to land on the Floating Continent from the airship, you are puzzlingly told that you can only take three people along, even though the party limit is four. You find out later that but still. At the time you can't help wondering what part of this whole plan would be messed up if one extra person went with you.
 * Before that, on the haunted train, you may recruit ghosts to have up to four party members, but if you try for a fifth member, Sabin objects that too many members would slow you down. Frankly, in an area that dangerous, I'd take slow over weak.
 * Later on in The Very Definitely Final Dungeon, though you still have the same party limit, you need to form three parties in order to reach the Big Bad. The 3 parties merge upon reaching the Big Bad into a party of 12, while you still fight in groups of four, once the ones in battle are all KO'd, they would be switched with the next in the line up.
 * Justified in Final Fantasy VII. Near the beginning of the game, when the number of allies travelling with the main character exceeds the 'recommended' amount, they split into two groups and arrange to meet up at the next plot-relevant location because, technically, they are all wanted terrorists. It is essentially decided that, since the antagonists are searching for a group of 5 people, they wouldn't stop to question a group of 3 and a group of 2 moving separately.
 * Averted during the final Boss Battle. Normally, the player controls one group of 3 characters during a battle, but when fighting the Big Bad the player is allowed to equip ALL 8 characters and may cycle between them at any point in the battle, if it seems like one group is struggling to make progress alone. Not unique, but certainly unusual among RPGs to allow the entire cast to take part in a fight.
 * Then, you have the Fort Condor proto-RTS sequences. The gist of these, according to the inhabitants of the fort, is that they have to hire mercenaries in order to repel attacks by the Shinra. Naturally, they ask you for your monetary contribution. Eventually, you are forced to take an active role as commander, and this involves buying the services of various units and placing them around the battlefield. Arbitrary Headcount Limit rears its ugly head here, because you are limited to placing a maximum of twenty. By the time you reach this sequence, it is entirely possible that you have enough money to fill every square foot of the battlefield with units.
 * Final Fantasy IX deals with this trope in several different ways. At the very beginning, you only have three or four characters in the party at a time, with the guest character getting a bridge dropped on him to make room for the fourth. Later on, when the fifth main character appears, the party splits up into two groups, each of which can accommodate the Abritrary Headcount Limit. When the two parties reunite, some of the characters are Put on a Bus for the rest of the disk to make room for the final party members. When the entire party unites at the start of Disk 3, they are frequently seen gathering in various dungeons, sometimes offering explanations as to why they split up again, but by the final few dungeons it's assumed that the entire party is travelling together, and the fact that whichever four characters the player isn't using don't seem to be doing anything is pretty much Hand Waved.
 * Final Fantasy X and Final Fantasy XII limit you to three characters at a time. X uses a Lazy Backup tag system so if all three characters get KO'd, you're screwed, but XII allows the "sideline" characters to rotate in at any time.
 * Final Fantasy XII Revenant Wings however makes the arbitrary headcount 5 but that is because it is a real time strategy game. One does wonder however why the other 4 characters are not allowed in battle when your army size can be maximized to theoretically 45 members.
 * It should be noted though that you can also rotate in your sideline characters during the middle of a fight in FFX, you just can't rotate out a KO'd character unless you revive them first.
 * Justified in Phantasy Star IV. Until the end of the game there are only five characters in your group at any given time, and when everyone finally gets together to fight the Big Bad, there are only five artifacts of power that'll let their wearers go into the lair. Of course, this is somewhat moot, as the fifth of those artifacts (the Rykros ring) was not actually equippable by any of the characters; no matter who you picked, your fifth party member didn't get one anyway.
 * The Quote at the top of the page referenced Phantasy Star 2 which did have an arbitrary limit on party size. Phantasy Star and Phantasy Star 3 both get around this by having the size reflect the maximum characters availble at any given point. Phantasy Star 2 however just randomly limits the size of the party.
 * Rolf's solo adventure spinoff states he dislikes working with others and would rather have a small team if he HAS to bring one along, since small teams mean less chances for others to mess up. Since he is basically team leader, that is very likely the reason why he only brings a handful of people along.
 * The entirety of the Tales (series) has four as this number, with the actual party size ranging from five six (Phantasia) to nine (Destiny). What, if anything, the extra members are doing while the others are fighting is never explained, barring a fight in Abyss where the two extra members have to secure an escape route.
 * Tempest, Innocence and Hearts have a limit of three. The GBA Narikiri Dungeon games also had four parties of three each, but since the actual party size was every character in the first five games...
 * Hearts also averts it, like Mugen no Frontier above, by introducing the "Link Attack" system, by which characters in the back party can be summoned in to use attacks or spells. Since characters Linked in can't be damaged or interrupted, it's useful for calling out a Raise Dead or Last-Disc Magic with a charge time of "eternity".
 * Lampshaded in Tales of Symphonia:

So, uh... the other 4 were just sitting off to the sidelines, maybe eating some curry? Granted, we're talking about a trope here, but the Lampshade is hilarious."


 * Similarly, if you go a long time without switching party members in Tales of Vesperia, you may get a skit where the inactive members complain about being left out of the action. Yes, the others really are just sitting on the sidelines.
 * In Golden Sun The Lost Age, you eventually acquire a party twice as large as the cap of 4 in battle, the result is the ability to switch a single character from the team in battle with one in the 'on hold' team per turn, and should all 4 of your party get knocked out they would instantly be swapped with the back team.
 * Riviera: The Promised Land lampshades this by stating that going into battle with more than 3 members would make things too crowded, but this does not explain why battling party members can't tag out.
 * In Brave Story: New Traveler, you can not control more than three people in the party, one of them being your character.
 * The Last Remnant has an extremely generous limit that increases over time.
 * In Skies of Arcadia, the four-person party is mostly explained by the plot -- the main trio are bestest friends and stick together, while the fourth slot is occupied by whoever's present for the plot at the time. The game really runs into an Arbitrary Headcount Limit towards the end, however -- you can pick who to take with you into The Very Definitely Final Dungeon, but taking more than one of the fourth-slot characters is forbidden. The crew of your Cool Airship is also limited. You can recruit 2 crewmembers for each position but only one can be on duty, even if the job is in no way exclusive like "sailor" or "merchant".
 * Parodied in Dragon Quest IV. At the beginning of chapter five when the hero first enters Branca, a four-person team is leaving the town. If you talk to them, one will tell you that their party is full and that you'll need to find another one to join.
 * Played painfully straight in Dragon Quest VII, though, which sticks to the series' usual four-person party... when there's only five main heroes. Leading to a few Contrived Coincidences to keep that one extra hero distracted until it's time to rotate again...
 * Last Scenario only lets you use 4 of your characters. This is made even weirder because the cutscenes make it clear that the whole party is traveling with you.
 * The spiritual sequel Exit Fate had a party limit of eight out of... seventy-five. Also, two of those eight occupy the entourage, and cannot fight, but any of the other six may spend an action to trade places with them. Exactly why two people who are officially employed soldiers decide to cheer from the sidelines instead of aiding their teammates is not clearly explained.
 * The main Pokémon games only allow you six Pokemon at a time, while the rest are kept to the PC; it's justified in the Pokémon Special manga as a rule imposed by the Pokemon League due to the fact it would be difficult for a single trainer to care for more Pokemon than that at a time. Pokémon Ranger gives you a limit of seven. Pokémon Mystery Dungeon gives you a limit of four as well as an overall size limit; it can't exceed six stars, even if it's just two Pokemon.
 * In Star Ocean the Second Story you can have 8 characters, but only 4 in combat. By default you'll get a choice of something like 6-7 (on top of the two mandatory) - but the entire game you can refuse members, or get hidden/secret ones, meaning the minimum is 2 party members, with 9 choices. That's out of a total pool of something like 10 choices, as choosing the male/female lead will make a different person impossible to get.
 * This is also done in Star Ocean 1, but one gets a little less choice over the characters, as four are required (Meaning you only get to pick the other four, compare six in the second game) and only one can be booted. (The Enhanced Remake also gives you the chance to not exactly boot her, but get a better character who is a hidden character)
 * In addition one is fairly difficult to find without an FAQ, while another will only become available fairly late in... at which point you've probably already filled up all seats.
 * Valkyrie Profile always has quite a bit of playable characters but only three manifest at once. This is explained with how Valkyrie only manifests the einherjar that she wishes to train. Except that there is one game in the series that doesn't actually have a Valkyrie as the main character...
 * Valkyrie Profile Covenant of the Plume stars a mortal named Wylfred who is required for just about every battle, but three people join him in battle. From a gameplay perspective, this makes total sense. (Because considering you can recruit up to 9 characters in the main story and way more in the Seraphic Gate...how on earth would you be able to pull that off on a handheld?)
 * Justified in The Reconstruction by Wadassian law restricting your guild to six armed combatants at a time.
 * And then.
 * Infinite Undiscovery allows 4 characters, or 3 if one of them is Gustav. Out of 18. And some of them are arbitrarily forbidden from being in the same group as the Player Character, restricting their use to Let's Split Up, Gang!-situations -- without the slightest explanation.
 * Lost Odyssey has a limit of 5. Even though the formation interface has 10 positions, you're only allowed to fill half of them.
 * Played agonizingly straight in Suikoden. You have an entire army, but you can only take six at a time. Suikoden III added a seventh slot for 'support' characters.
 * In Suikoden IV, this was downsized to a four-person party, plus a 'support' NPC. After this proved unpopular with players, Suikoden V responded by upping the limit to ten -- while you could only have up to six actively fighting in your party at any given time, there were four extra slots you could use to bring along other characters, be they supporting NPCs or other fighters. This helped with Leaked Experience and provided an alternative whenever you had to bring certain characters along for plot-related purposes.
 * There's a bit of missable dialogue with your strategist that actually explains this: when going on land, you have to be careful not to attract undue attention, so a small party is better unless you want the whole Kooluk army (which vastly outnumbers you, to say the least) on your tail. As for the ship, you are restricted to 3 parties (12 people total), but they are freely switchable in battle, and that's because there's not enough space for more to fight on the ship, since the rest of the space is taken up by the currently-attacking monsters and overcrowding the ship's bridge can result in someone getting shoved overboard in the confusion.
 * The Etrian Odyssey series allows you to have a decently sized Guild, but you can only have up to five members in your adventuring party at any given time. Word of God admitted that this was meant to make players feel their parties were always "incomplete" somehow; six-member parties were simply too well-balanced for a game striving to be Nintendo Hard.
 * In Endless Frontier, your entire party can participate in battle, but only four are active and fit on the screen. The non-active characters can use support attacks during the fight, up to certain limits, with some characters only capable of participating through support attacks. The sequel shows off how arbitrary the limitation really is, with a lot more support-only characters, one character who has a partner, and still the same four-character headcount limit.
 * Breath of Fire II only allows four characters in the main party at once, while the rest remain in Player Headquarters. Mind you, this is the game with the largest number of Player Characters in the series, at nine. III also had this problem, allowing only a party of three out of six. The rest of the games, however, avert both this trope and Lazy Backup, or, in the case of Breath of Fire: Dragon Quarter, all your party members participate (then again, Dragon Quarter's playable cast was reduced to only three).
 * Completely and totally averted in the case of Lunar: Silver Star Harmony. When you enter battle, all party members participate and can be controlled.
 * Kingdom Hearts only allows you to use three characters at a time... which seems more than a little pointless, given you never have access to more than four at a time anyway, and given that all experience is leaked.
 * Shin Megami Tensei games typically have a limit of 4-6 party members, including the protagonist. This is somewhat justified by the fact that the device you're using to summon your allies can only keep so many of your demonic allies manifested at a time. This doesn't explain why human party members take up one of those headcount limit slots, however...
 * The Persona subseries of games justifies this in the first four games, and then plays it completely straight in the fifth. In Persona 1, there were eight possible party members aside from the protagonist. Depending on which quest you were on, one to three of those slots was locked in. The remaining slots could be filled at key points in the story, but once your party was full, additional party members were immediately sent to safety. The Persona 2 Duology also had a cap of five, but (with a single exception in Eternal Punishment) you don't get to select which party members will fill those slots.
 * Persona 3 justifies this by having the party be an exploration team. That way, if the entire team bites it, SEES won't be wiped out. (...Well, )
 * During the Final Battle, when all of SEES is present at the Boss Arena, the limit is justified when Fuuka detects a large number of Shadows climbing up towards them. Mitsuru commands the rest of the party to Hold the Line against these Shadows and defend the main group while these fight the final enemy.
 * Persona 4 looks like it has a similar set up as the prequel... but then the entire party inexplicably shows up in the final room of each dungeon. There is, admittedly, a portal leading there from the lobby. The only reason why the unused party members wouldn't be fighting is because you've spent the entire game up to this point playing with Yosuke, Chie, and Yukiko, while Kanji, Teddie, and Naoto don't even have upgraded equipment, let alone levels.
 * It's at least partially explained when you revisit a dungeon. Occasionally, members of your party that aren't actually with you can randomly appear in an empty room of the dungeon. It's implied that they've formed an independent B-team and fight Shadows in other parts of the dungeon. Of course, you never see the products of this endeavor.
 * In Devil Survivor, you can never have more than four humans on the field (counting the main character).
 * Sweet Home has a limit of three members per party. If you try to have a fourth join, the other character will say that it would be best if the fourth character stays separate. If a character rescues the fourth from a pit, one of the original three will be disconnected from the party.
 * Secret of Mana and Seiken Densetsu 3 have this for the enemies, only allowing up to three on screen at once.
 * Inazuma Eleven has an amazing number of 100 members allowed at any one time, but given its Cast of Snowflakes, arguably even that number isn't enough. As with soccer, during matches 11 members are on-field while optionally 5 are on bench.
 * Wild Arms 4 only allows you to have 3 characters in battle out of the 6 playable characters. This is down from 4 in the previous game.
 * Subverted in Blue Dragon, everyone joins the fight for huge battles.
 * Played with in Shining the Holy Ark where only four characters can appear at a single time in battle. However you could freely switch characters over, so if a character is killed you could replace them provided you had another character to take their place.

RPG -- MMO

 * In Runescape, you are only allowed to have one follower, either it be a pet, summoning familiar, or someone relevant to a quest.
 * Guild Wars imposes an Arbitrary Headcount Limit in every area of the game, including outposts, where players can't even fight. In the training area it's 2; in low-level areas it's 4-6; in the high-level areas it's 8; and in elite areas it's 8-12. Usually, this limit isn't a big deal, since low-level areas are balanced for small teams. But just see what happens when a team of 4 tries to kill things in the same newbie area in hard mode...
 * Originally, players could only have 3 heroes in their party at any given time, despite having access to almost 30. These days it's possible to bring 7.
 * In Star Wars: The Old Republic, each character eventually accumulates six companions in their party. Only one companion may be active at a given time.

RPG -- Western

 * While most tabletop-derived CRPGs simply insist that you cough up some party members whenever you recruit more than 3-6 for no particular reason (I'm looking at YOU KoTOR!), Fallout II gave your character a statistical limit on their ability to schmooze people into following them, based primarily on charisma (the first game had no limit, but there were only five recruitable characters anyway).
 * Fallout 3 limits you to one follower and a dog at one time, no matter what your stats are. However, by engaging in some trickery you can swap the dog for another follower. And convince some quest-driven NPCs to follow you by promising to take them somewhere, and then never actually going.
 * You can glitch in as many followers as you want. The trick is to fire a follower, talk to the lender (Eulogy Jones or Tinker Joe), and immediately re-hire the fired follower before the new follower talks to you. Apparently, Star Paladin Cross joins you if you have good karma and talk like a good character regardless of party count. There's also a trick to get Fawkes as well. Note that this is one method of gaining followers, there are many others (mods).
 * And with a new DLC for the game, with a perk, the dog respawns. You can kill the dog while in the same room as the guy you want to hire, and just hire the new person. And the dog will respawn in 24 hours (game time). Rinse and repeat.
 * In the Operation:Anchorage DLC, you are tasked with leading a squad to several objectives and eliminating the Commies therein. You have an amount of tokens, and different kinds of troops use different numbers of tokens depending on how strong they are. For example, a soldier with a rifle will take up 1 token, while a Mr. Gutsy will take up 5. The reason supplied is that too large a force will tip off the Commies that you're attacking.
 * The Shadowrun game for Super Nintendo similarly limited how many runners you could hire based on your charisma.
 * The Sega Genesis version limited you to three, period.
 * The Lord of the Rings: The Third Age has a very strange one: Any person on the battlefield can switch out for any one not on the battlefield at any time, but only three can actually fight at one time. And if someone gets knocked out? Nobody will fill in for them. They just lie there, taking up a perfectly good slot. To make matters worse, there are occasionally guest characters who can't be switched out, even if they're very poorly suited to whatever enemy you're up against at the time.
 * BioWare is fond of this trope:
 * Baldur's Gate deserves a special mention here because not only is your party restricted on size (6 maximum) but also on philosophical differences. If you get too popular with the rabble, the more buttkicking evil characters in the party will simply up and leave. On the other hand, the whole Dungeons and Dragons system is keyed to this, mostly because the calculation of what monsters constitute a challenge for a party depend on the said party being 4-6 strong.
 * Baldurs Gate II. Specifically coming to save a friend of yours, but not being able to lead her out of the dungeon of the Big Bad because your party was full (There actually was a dialogue option that said this). At least Bioware added an optional NPC that would betray you at a very convenient time, opening a slot for the Damsel in Distress, if you had him with you.
 * In the original Neverwinter Nights, you could only have one henchman at any one time. Hordes of the Underdark expanded this to two, but still required you to leave three or four perfectly capable allies waiting around back at base in the first chapter. Fan-made modules occasionally remove this limit entirely, leading to annoying situations like the mines in the second chapter of A Dance With Rogues, where you have to individually command six different party members to stay where they are while you set off an explosion to clear a tunnel and then command them all to follow you again.
 * In Neverwinter Nights 2, you can have as many as ten party members, but you can never have more than 3 with you at once - except for Shandra, who doesn't count towards the limit. For some reason, after, the limit remains at 4.
 * Neverwinter Nights 2 started out with allowing you three followers, then increased the limit over the course of the game without much explanation. In the final battle, you're controlling every single member of your group, so one wonders why no one thought to do this when fighting any of the other big bads. Meta-game-wise, it's mostly because it's very difficult for the player to keep track of so many characters.
 * Particularly galling in Mask of the Betrayer, where you have only four potential companions at any time but can only take three with you, and all of them have their juicy personal relation to the main plot that you'd inevitably be missing out on.
 * Mask of the Betrayer is particularly annoying in this regard. You can take up to three companions with you, but there are only four in the first place. (To be more precise, the game has five different companions, but two are mutually exclusive and after you pick one, the other doesn't even become a companion option, so you have access to four and not five.)
 * In both Knights of the Old Republic games, you quickly acquire a party of 8 or so characters, but can only ever wander around the planet with two characters other than yourself.
 * Jade Empire is even worse given that only one other character can join you at a time.
 * Additionaly, one of these does not fight but only allows you to use the Drunken Master style. Another character is in your party pool but is only there to trade with you. With him being a disembodied spirit, this makes a little sense.
 * Mass Effect does it too, and there's no particular handwave for it. Four of the NPC's aren't even part of the ship's crew, so it's not like they are needed on board. The other two are marines, so they wouldn't be much help in a starship battle. It's never explained why Shepard can't take the entire group of 6 with him/her. Especially when the entire universe is in the balance. In fact, the only person in the party who would have a logical reason to remain on the ship is the Player Character him/herself, as he/she is the ship's Commanding Officer.
 * Mass Effect 2 also plays it straight, except for The Very Definitely Final Dungeon where the whole team gets to participate. Still only two can come with you, but the others are blasting their way through another path or holding the line while you fight the Final Boss.
 * The only other time the entire team goes away on a "mission", it is explained that Shepard would then choose who to take with him/her when they get to their destination. The "mission" is actually a.
 * Particularly jarring in the Lair of the Shadow Broker DLC, as after meeting up with Liara, you are prompted to choose which one of your teammates to take with you, despite there being absolutely no point to leaving one of them behind. Sure, it makes some sense to leave part of the team behind on the Normandy, but in this case, there is literally no reason for this other than the headcount limit. Made even more ridiculous by the fact that the group of three then enters a skycar - which explicitly has four seats.
 * Sonic Chronicles limits you at four with Sonic always in the lead. Counting Cream and Omega, you can have eleven.
 * True for Dragon Age: Origins as well. You'd think as one of the only two people able to stop a horde from destroying the world, you'd be able to take all your companions into battle, but you're limited to a party of four. Unlike the other games, though, during the final battle in, all your companions join the initial assault. Then you make your party selections for the final boss battle, leaving the rest to defend the gates. Kudos to Bioware for actually letting the players control the remaining companions during the defense (the only time in the game where the party does not include the main player).
 * In Dragon Age II, the three-companion limit is justified for most of the game by the fact that most of Hawke's companions are established as having their own lives and things to do outside of running around with Hawke. Aveline has a day job with the city guard, Anders runs a clinic in Darktown, Varric is a writer and is implied to have other business going on as well, Merrill is working on restoring the Eluvian, Isabela is trying to track down her relic and Sebastian is working for the Chantry; only Fenris and (in the first act) Hawke's sibling seem to have nothing better to do. However, on the two separate occasions when all hell breaks loose all over Kirkwall and the survival of potentially everyone in the city hangs in the balance, it makes considerably less sense that half your friends see fit to sit this one out.
 * Planescape: Torment is actually a fair bit better with this. The party can have up to six people, counting the Nameless One. There are only eight recruitable characters, and one of them is almost universally considered The Load, and another is a batshit insane Knight Templar who even a good aligned Nameless One probably wouldn't want.
 * In Dungeon Siege, your party is arbitrarily limited to 8 characters. Once full, you have to abandon existing characters when you want to recruit new ones. Your pack mules are included in this, so counter-intuitively your party can keep track of less animals as there are more of you.
 * Frustratingly, to a mind-boggling degree, you don't start with the ability to have a maximum-size party in Dungeon Siege 2. You start with two and have to find an NPC and purchase the right to have progressively more active party members at one time. You can't reach the real limit until you've already beaten the game twice.
 * The blow is arguably lessened to a degree due to the fact that the first 4 potential party members you come across are one of each of the four main classes (Lothar the warrior, Deru the archer, Taar the Nature Mage, and Finala the combat mage).
 * On the surface, Geneforge is generous about this, with a party limit of eight. Due to the way your Mons work, you'd have a hard time getting more than five anyway. Then again, there's also the matter of the experience penalties for large parties, which seem designed to make you not want more than eight party members anyways.
 *  Might and Magic had this, though in different ways in different chapters:
 * I to V had parties restricted to six (I, IV-V) or eight (II and III), in-game creation and switching out of characters at inns, and no explanation for why a larger party would not have worked. The two extra slots in II and III could only be filled with hirelings, who would desert the party when you rested if you couldn't pay their wage from your gold on hand.
 * VI, VII and IX had a party of four, with all created at start, and reasons for them not expanding ... but one could also recruit up to two 'followers' that gave some perks, with no explanation given for why three followers were one too many. VIII had parties of five, with one created at start and unable to be switched out, and others found as the game progresses, but no explanation for why, once you have that many adventurers, any excess over five has to stay at the inn.
 * Ultima had this in many of the games. In Ultima IV you are limited to 8 party members and there are 8 recruitable, but the game dictates that you cannot recruit whichever NPC matches your class. V-VII play this totally straight.
 * Mount and Blade has a limit to the amount of lieutenants and soldiers that can be added to the party at any one time. However, this limit can be increased by raising your charisma statistic when you level up, or by increasing your renown by winning battles, and there is no upper limit on how high you can raise your party cap.
 * Skyrim only lets you have one companion at a time, just like Fallout 3, and it doesn't even attempt to explain why. If you ask someone else to join you, they'll just say "Looks like you already have someone following you."
 * In Evil Islands, you can't have more than two allies at a time, although Lazy Backup is avoided and you can just pick another one if one of them is killed.

Shooters

 * In the Star Wars Battlefront games, bots are limited to a maximum of thirty two per side. However modders have found that by altering a few lines of script in their mod maps, they can have battles with over a hundred troops on the battlefield at any given time. Granted, a hundred soliders on the Tantive IV would probably be overkill, but it would make sense for those large outdoor levels.
 * The ill-fated Jurassic Park: Trespasser, rushed to completion for the sake of deadlines, had to be released long before many of its reliability and performance issues could be resolved. Lots of cool ideas were abandoned, along with one entire level, because they just couldn't get them working in that amount of time. The quick fix they introduced to minimize, at the very least, the rampant in-game slowdown? They coded in a hard limit on the number of dinosaurs the engine could generate per level. Seven. Of any kind, hostile or non-hostile, something you have to fight or something that's standing off in the background and completely irrelevant. The total can't exceed seven.
 * Within a certain distance. There can be more than seven, but they just stand there, being invincible and doing nothing until you get within the required distance. This makes long range combat even more infeasible.
 * In Operation Flashpoint, squads are limited to twelve soldiers at a time, including the leader. This is due to technical limitations: squadmates are selected with the function keys. The AI is also affected by this as the mission editor won't let you link more than twelve soldiers into a squad.
 * "Tactical" shooters like Rainbow Six or SWAT 4 give you long, impressive-looking rosters of potential teammates to aid you in your missions... then limit you to a small squad of operators regardless of the size of the level. Particularly glaring when you're asked to clear large structures - cargo ships, oil rigs, warehouses, hospitals - with less than 10 people.
 * Justified in that, by definition, these type of games involve an small elite unit trained to take hostiles in different enviroments as quickly and silently as possible. Sure, they limit the number of operatives you use; if they didn't have said limitations during the operation, why not send an entire army and solve the problem just like that?
 * Postal 2 has a form of this - there is an option to limit the amount of people spawned in one map area at a time, to prevent overloading and causing the game to crash. Depending on the player's setup, one can increase that number for more carnage.
 * In Thwaite, if ten houses are already present when morning comes, another house is not built.

Simulation Games

 * Many combat flight simulations, such as B-17: The Mighty Eighth or IL-2 Sturmovik have a limit to the number of planes in a given scenario. This means that the player's 3 or 4 fighters are typically attacking enemy bomber formations of 8-12, rather than the 80-100 common in the Battle of Britain, with predictably catastrophic results for the bombers.
 * In The Sims 2 and The Sims 3, you're only allowed to have eight Sims per family. The game still works just fine if you use a cheat to raise the limit.
 * Modifications have also been released that alter this limit. One even allows you to go all the way to fifty.
 * Aerobiz: The first two games limit your airline to no more then 40 total flight routes. Frustrating in the second game due to how the region system works and the fact that there are about 90 or so cities in the game.

Strategy -- 4X

 * The older Civilization games had an Arbitrary City Count Limit (255 for Civ2, to be specific). The table of cities only had room for 255 entries
 * Civilization IV implements a more typical Cap, forbidding each civilization from having more than three missionaries of a given religion at any given time. However, since missionaries are self-consuming, the limit is not nearly as annoying.
 * Civilization V revamps the resource system to work this way. In the previous two iterations, you just had to have the resource—eg. you needed Iron to create Swordsmen, because Swords are made out of iron —unless you were playing Civ3, at which point the resources depleted at an unexplained rate. As of Civ5, Resources are now an Abritrary Building Limit on how many of a thing you can create at once: if you want all six of your cities to spawn Swordsmen but you only have four units of Iron, then two of them will have to do something else.
 * This can get annoying, as conquering civilizations will tend to have a lot of puppet cities, whose government cannot be influenced for some reason (isn't that the whole point of a puppet government that they do what you want?), so they continue to build nuclear power plants when you're desperately need your few uranium deposits to build nukes/submarines/HumongousMecha. There should at least be an option to restrict any construction that requires strategic resources. As the ruler of that civilization, you should have the final say on resource allocation.
 * Averted in Master of Orion II. Each of your star bases would generate a certain number of "Command Points" for your empire, representing the capacity of your logistics to manage, maintain and command ships. All the military ships in your empire counted against the number of Command Points you had, with larger ships costing more. If you happened to exceed your Command Points through overbuilding or loss of facilities, you had to pay for the difference in cash, every turn, until you either replaced/recaptured facilities or reduced the size of your fleet.
 * But not pay all that much. A gaming magazine's retrospective featured an image of a fleet of death stars, with the caption "This is what they were trying to avoid."
 * Sword of the Stars doesn't limit the size of the fleets, but it does limit how many ships that can participate in a battle at each moment. Each side gets command points based on on the size of the command ship (if any), some technology upgrades, and if they outnumber their opponent; when a ship gets destroyed (freeing up associated command points), new ship(s) will arrive as a reinforcements from the reserve.

Strategy -- Real Time

 * Averted by Harpoon. You can recreate a scenario like 3 or 4 US Carrier Groups escorting a massive amphibious assault convoy vs the entire Soviet Navy. Or you can recreate an attack by North Korea, China and Eastern Russian forces vs South Korea, Japan and the USA if you like. The only limit is your computer processing power.
 * In Homeworld, there is a limit as to how many ships can be built by your own ship construction facilities. This could be justified with Fleet Command being unable to direct more at one time, or not having enough crews to man more vessels, if it weren't for the fact that one can go far beyond this limit by capturing enemy ships and adding them to one's own fleet.
 * However, in the sequels, breaking the headcount limit is stopped: all ships, captured or built, are counted under the fleet cap (and a capture that failed because of this didn't even have the decency to scuttle the ship).
 * Moreover, the limit is on ships of a given size - 50 fighters of any kind, xx corvettes of any kind, 18 frigates of any kind, 4 destroyers, 4 carriers, and three cruisers) - which could lead to not being able to build more fighters but being quite capable of building a whole pile of corvettes that would all be turned to scrap metal in under three seconds.
 * Except one: Hiigaran Mothership/Vaygr Flagship. It is possible (as far as official 1.1 patch is concerned) to have a 6-player match and ending up with each player's flagship as your own. Didn't See That Coming did you?
 * In the Warcraft games, one must build farms in order to have units, with the limit increasing with the number of farms built. The rationale for this is that the units need food. Yet sometimes one starts a scenario without any farms at all, or an inadequate number to feed one's troops, or your farms in a normal level get destroyed. Said units suffer no ill effects for this.
 * In Warcraft II there is a hidden limit of 600 units (and buildings) divided by the number of players. (Meaning only 75 per player in an eight player game.) Extraneous units simply disappear when their construction completes, wasting resources.
 * In Warcraft III, there is also a global supply limit of 90 (raised to 100 in the expansion) on the total number of units a player can train (although it is possible to go over this limit if the extra units are acquired via means other than training, like resurrection spells or a scenario script). Unlike Starcraft, there is only one supply pool (as opposed to a separate one for each race), and the limit thus cannot be circumvented by building units of different races.
 * Most units require between 2 and 5 supplies in this game however, limiting a normal army to about 20 units at most.
 * It's also worth noting that if you want a higher supply limit (assuming it's a non-campaign map), changing the Game Values is possible, though it only goes up to 300. However, the game's engine can't seem to handle more than about 250 units per player-- if more are generated through scripts or other tricks, movements become very erratic.
 * You can also change the supply requirements of the units, including setting them to zero.
 * In Starcraft, one could only have a maximum of 200 supply worth of units on one's side; if you tried to make another after the limit was reached, it simply wouldn't work. However, in the Expansion Pack, Starcraft: Brood War, the "Dark Archon" could capture the other side's worker units, thus allowing you to create buildings and build up to 200 of each of the three races in the game.
 * The Dark Archon can also capture units in excess of the Arbitrary Headcount Limit. In a team game, it is possible to exploit this to create a ridiculously huge army; Player A cranks out unit after unit, while player B methodically seizes control of each unit with Dark Archons. Not usually a very effective tactic (most games are over long before anyone hits the cap), but amusing.
 * The Unit Limit in Starcraft was put in place not as a balancing factor, but to prevent players from building units in excess of what the game could process. Despite this, it is possible for a Zerg player to force the game's memory out by building Overlords (the only unit in the game that does not use up supply) en masse, causing units to stop spawning when the game runs out of memory. Not a very useful tactic in high-level play, due to the tendency of games to end quickly, and the resource limit imposed by most maps.
 * It's also possible to construct so many buildings that the game won't allow any more units to be built (or any more buildings, for that matter)-- discovered when using Dark Archons to sieze an ally's Carriers; additional Interceptors couldn't be built until some building were razed.
 * This has been an issue with Terran Valkyries as well, who shoot several missiles in a broad area. The missiles can sometimes not fire because of the aforementioned technical limitations. This was cited as a reason, though not the main one, for the lack of Valkyries in the Metagame.
 * With the use of cheat codes, it's possible to make the game crash itself in missions where the AI receives infinite units after an event trigger. Try using "Staying Alive" on Terran Mission 9 in the first game.
 * It sure wreaks hell on a great many Use Map Settings games featuring trigger-spawns of many units, and hundreds of buildings across the map. The "Cannot Create More Units" is so bad in maps like "The World in the 1800s" that the game literally begins to drop players en masse.
 * Starcraft II has the Protoss Mothership, a unit which uses no normal supplies, but of which there can only be one at a time (per player), or which can be built like any other unit (i.e. as many as you can afford) but costs a metric fuckton of resources - Blizzard is still working on that.
 * Both averted and played straight with the Total War games. You can build as many units as you want, provided you can maintain their upkeep. However, in battle, you are limited to twenty units per army stack. On the maximum scale settings, this can give you a maximum of 4800 soldiers to command in a single battle. In Rome, this is a bit of Fridge Brilliance, since that number isn't far off from the total number of fighting men in a Roman Legion. (Not counting the thousands of support soldiers)
 * Every Age of Empires... game had a headcount limit. This is particularly ridiculous, since the Age of... games are supposed to portray great battles of times long gone, which were normally conducted with hundreds and hundreds of men. The first Age of Empires I had a unit limit of fifty! However, it is possible to convert enemy units using priests to go indefinitely beyond this cap. Additionally, all units built before the population limit is reached will be completed regardless. Employees of Ensemble, the company that developed Age of Empires, were famous for building, for example, 20 barracks at 49/50 population and queuing each building to produce one soldier, which gave them 19 units over the limit.
 * In the original game's expansion set "Rise of Rome", the technology "logistics" allow infantry to count as 1/2 a unit, thus allowing a larger army. The basic head count is also raised to 75.
 * This can be extended to 200 per player in the multiplayer mode (since each unit counts as 1, this limit is almost never reached), and the amount of units placed in the campaign editor is limited only by the power of the computer running the game.
 * Age of Empires III also includes headcount limits for certain unit types, most notably ships. Most Civs have a generous cap of 99 Settlers (half of your population cap), although the Ottomans, who produce Settlers automatically and for free, have a more substantial cap of 25 until you raise the limit via certain techs.
 * Certain special units have a Limit of One. Most notable is Age of Mythology, which has several of these units, including the Titans, the Hippocampus, and a few others. In one case, the clever combination of an Egyptian technological upgrade (allowing two Pharaohs) and a cheat code (allowing reuse of a god power that transforms a pharaoh into a lightning-wielding Son of Osiris) actually allows the player to create an infinite number of Sons of Osiris, provided he has enough houses for them all.
 * Age Of Mythology added a new feature to screw the headcount even further: some units take more space from the population slots than others (i.e. a villager or a simple soldier takes one; a siege weapon or a mythological unit can take up to five).
 * The game features a rather flexible limit, though. Every player can build houses for 100 slots and as many Town Centers as he can get a hand on (they can only be built on specific spots). They provide 25 slots each if upgraded, and a certain relic allows them to give 3 more, while the Citadel god power adds 10 slots to a town center, in addition to making it much harder to destroy.
 * The final max Arbitrary Headcount is 300, as can be demonstrated in the final level of the original campaign by building on as many locations as possible. We Have Reserves indeed.
 * There are also hard limits on the number of each type of building you can have.
 * The Command & Conquer series is notable for having no such limit, with the exception of a port on the Xbox 360, and some "Hero" units which are limited to one for each team.
 * Up to Command & Conquer 4, where one of the features include... a headcount limit.
 * Strangely, said headcount limit was variable between missions (even in skirmishes!), though you were usually limited to 60 points, and could break it by commandeering fallen enemy heavy vehicles. One upgrade brings your dead heavy vehicles back to life, even if that puts you over the limit. Build five Mammoth tanks, kill them, build five more and wait for the other five to come back to life, you've got ten, and you can repeat until everything else is dead.
 * Rise of Nations was fortunate to have a comparatively huge Headcount Limit of 250 units, which could be raised to 320 with the right combination of civilization (Bantu) and wonders (the Colossus). Some units, of course, count as two heads, but it still allows for some really, really big armies.
 * And that's assuming you don't mess around with the config files.
 * One of the earliest RTS games, Dune II, uses this as well -- however, in this case, the explanation could be the very real technical limitations of the PCs and Amigas the players of those days possessed. In its sequel, Emperor: Battle For Dune, the headcount limit was lifted.
 * It was also lifted in the remake, Dune 2000... but they forgot to update the AI to compensate, causing a bug where taking too long to make an attack against an enemy would cause them to have an army so vast that victory was impossible, as they were perfectly efficient at building units, and never stopped, expecting to run up against a hard-coded cap that no longer existed.
 * The original also kind of screwed up its limits. While you couldn't build anything beyond a limit of 25 units, you could Starport in anything up to a total of 99. This basically meant that your later armies consisted of about two Devastators (which can't be bought) and ninety-seven Siege Tanks (which can).
 * Incidentally, in Dune II, a similar limit existed for buildings. This was actually rather exploitable, since the building limit was global: if you reached the building cap, then you could prevent the enemy from rebuilding by destroying one of their buildings and immediately replacing it with one of your own.
 * Total Annihilation was released with a unit limit of 250 units per side. A patch was released that raised this limit to 500. The large modification community for that game had even found a way to increase the unit limit to 5000 units per side. Given that the game allowed for easy adding of new unit types up to 256 different units, 512 with a community made fix, that means you couldnt build one of unit avaible.
 * Supreme Commander, TA's spiritual sequel, has a default limit of 500 in multiplayer/skirmish games. It can be increased up to 1000, and also decreased to 250 (for the unlucky ones whose computers can't handle the amount of units in a capped-to-500 game. This tends to be particularly annoying in the last campaign missions, some of which start you off with 300 or more units and a maximum cap of 500. Editing the game files can theoretically increase the unit limit to arbitrary numbers, but the frame rate really starts suffering (even on high-end systems) after 800 or so, and going much above 1000 is guaranteed to cause a crash.
 * It's worth noting that in Supreme Commander everything you build (except walls) counts as a unit- not only tanks and aircraft, but power generators, point defence and radar systems.
 * It's also worth noting that for both TA and SC, these are purely technical, not balance, constraints---you could pump out hundreds of gigantic superunits (Krogoths, Monkeylords, etc.) rather than little tanks if you had the insane economic prowess required.
 * One could extrapolate that this is the maximum capacity of control for an ACU. However, doing so is just justification for what is, as stated, technical constraints. Otherwise calling in sACUs would theoretically raise such limits.
 * The Pikmin series of games caps the total number of Pikmin on the field at any one time at 100. If you try to spawn any more the main character notes that the Pikmin "refuse to come out."
 * World in Conflict has a variation of this, every player has a limited pool of reinforcement points to buy units with. Different in that losing an unit doesn't allow you to replace it immediately, the reinforcement points are instead regained slowly. Paratroops and light tanks ordered as tactical aids rather than as reinforcements for some reason don't count towards this, though.
 * In Warzone 2100 each player (a game can have up to 8 players) is allowed to have 300 units (though only a dozen or so trucks - the game's worker unit - are allowed). That cap is several times higher than the AI and pathfinding is able to handle though, resulting in that in long matches with several players on big maps, some units are unable to move or take minutes after being issued an order before they actually carry them out, and clouds of attacking VTOL bombers can slow even the fastest computer available to a crawl.
 * Also seen in Company of Heroes. This is mostly done to prevent tank-zerging (which is still possible to a limited extent). Your population cap is dependent on the number of resource points you control. If your cap is reduced, existing units do not suffer, but cannot be replaced.
 * Certain units are also capped; you can only ever deploy a single King Tiger to the battlefield in a game, and it costs an insane amount of resources to deploy as well as a considerable amount of your population cap.
 * US Armour players are also limited to 1 Pershing at a time, although replacements can be deployed. The Pershing is much weaker than the King Tiger however.
 * The same is employed on several defensive emplacements to reduce the effectiveness of turtling. A prime example is the German factions, who can deploy devastating Flak-88 anti-tank guns. They are effectively forced to choose between having an offense and a defense.
 * Empire Earth was pretty good about this; although it did have a unit cap, it was a unit cap for the entire game you were playing, and you were allowed to set it along with the rest of the game options. This meant that players with slow machines could have lower unit caps to compensate, while players for whom it didn't matter could have a max cap of 1200. Mind you, this was for the whole game, but even with the games maximum 8 players, that's still 150 units to play with. The game even had a building ingame that allowed you to steal a portion of everyone else's cap and add it to your own.
 * There was also a building that was used solely to contain up to 40 of your units, then return them. When inside, they are removed from the limit, but not from the game. So if you had the ressources, you could attack with an obscenely large numerical advantage.
 * End War hardcaps the units on the field for any given side to 12 - while also only allowing 6 infantry units, 2 artillery, and 1 command vehicle, as well. No real explanation is given for this.
 * Fan Wank - your forces are meant to be Elite Mooks, so it's likely it would be difficult to maintain any more for your faction. The fact they are instantly replenished? Well, it probably goes under Acceptable Breaks From Reality for most, which is the best I can come up with.
 * Star Wars: Empire At War and its expansion are interesting with this. There is both a population cap and a reinforcements cap. The population cap increase with every planet captured and every Space Station built and/or upgraded. The larger and more powerful a unit is, the more population it takes up (but heroes always take only one point). However, the tactical battle cap is different. In Space Battles, one can bring in 20 (Empire) or 25 (Rebellion) points' worth of ships, with each starship/fighter squadron/hero requiring the same amount of points they require in the Galactic Map. Land units always take one point (but most consist of multiple troops/vehicles), and there's a different system: the defender's limited to ten units, while the attacker is limited by the number of Reinforcement Points they capture; each contains a different number of points, and they are still limited to ten population points. It is justified, however, in that that there is a limit to how many units a certain amount of systems can support while still functioning normally.
 * Sins of a Solar Empire has this in spades. Your total number of ships is capped by a number called "supply", with different chips accounting for different amounts (a scout frigate might need 2, while an assult corvette could be 7 or 8). This limit starts out at 100 and can be increased with research, though doing so increases the upkeep deducted from your resource income. Then there are capital ships, which need a whopping fifty supply, and are limited by how many crews you have avaliable to man such sophisticated ships, which can again be increased with research. Each planet can also support only a limited number of logistic and military structures, and while this can be increased on a planet-by-planet basis, the highest possible cap is determined by planet type (a fully-developed asteroid can support fewer structures than a fully-developed terran planet, for instance).
 * There is one exception to this rule. The Advent Rapture capital ship has an ability, Dominate, which allows it to takeover enemy ships except capital ships. Used over a long period of time and without sustaining massive casualties, an Advent player can have a fleet that exceeds the capacity. However, the caveat is that you're unable to build any ships until the limit goes back into positive numbers.
 * In the Warlords: Battlecry series, there is no arbitrary limit: you can build as many units as your buildings + charisma + upgrades provide room for. However, the games do have a tendency to crash, especially as the number of units on the map increase, so building ludicrously huge armies is generally not possible before you suffer a precipitous crash to desktop.
 * In Little Kings Story you can only have as many troops following you as you have badges for them. Apparently, no one's going to fight for a king that doesn't hand out shiny badges.
 * Star Wars: Rebellion has "maintenance points". Every planet you control gives you a certain amount of maintenance points. Planets also generate raw materials in their mines. Raw materials can then be refined with refineries; you have to pay a one-time cost in refined materials, but it also takes maintenance points, which return to you after the object is destroyed. You're further limited to eight groups of capital ships and four groups of starfighters. But that's not an actual limit on the size of your fleet; it just means you start having to conflate different ones. (In the case of starfighters, they're typically arranged by model, with the most popular model being split into two or three (or if all that model, four, as can happen when you're the Empire and your only decent fighter is the TIE Defender) groups. Finally, you can only have one Commander, Admiral, and General in a given fleet.
 * Maintenance actually comes not from planets, but from the resource units: Mines and Refineries. Each pair of Mine and Refinery you have gives you 50 units of maintenance, even if they're on the other side of the galaxy from each other. Mines and Refineries are the ONLY units that do not require maintenance to build. An interesting deviation is that you DO in fact need the maintenance to keep your stuff alive: if your maintenance for whatever reason ever goes negative, EVERY UNIT AND STRUCTURE YOU OWN is in danger of spontaneously exploding. A further variation is that if a planet is blockaded, all resources from that planet are blocked, which can send you into negative maintenance if you're running it too tight. Being able to sabotage pretty much anything, capture planets, bombard their structures into slag, incite uprisings to take them, and a few other ways of generally screwing with them; means that deliberately depriving your opponent of maintenance is actually an EXTREMELY effective strategy. When they've got nothing but characters left, they can't really fight back. And as for the space battles...the key thing there is the groups are just semi-arbitrary divisions for the purposes of mass-assigning orders, and can be of arbitrarily large size. The capital ship groups you can redesignate, and even order ships around individually. Fighters on the other hand...not so much. Of course, when you realize that each one of those on-screen fighters is actually an entire SQUADRON and you have over 100 of them...
 * Heavily averted in Cossacks: European Wars. Apart from having adequate housing, population is limited by food, which is a harvestable resource that is tracked, just like gold or iron, and is depleted continuously based on population. If food reaches zero, units start to starve to death.
 * It's not averted at all, the game still has an 8,000 unit limit (bigger in the expansions), it's just that with all the units costing food (except the mercenaries, who cost gold) you rarely have enough of the stuff to 'reach' the limit.
 * Mostly averted in "Empires: Dawn of the Modern World" which allowed games with up to 75,000 population.
 * Warhammer 40,000: Dawn of War likewise has a max limit for the number of units that can be requisitioned (similar to the point system used to limit the size of armies in the tabletop war game it is based on).
 * Furthermore, the Expansion Pack Dark Crusade takes this concept further by limiting the availability of certain of the more powerful units in the game to a number below what resources and the regular "unit cap" would allow for (though such units may still be purchased and queued up to be fielded, once the original units are lost). Again, in many cases this is based on field allowances in the tabletop version. For example, the Imperial Guard is limited to having two of their Leman Russ main battle tanks on the field at a time - ie by real-world measures you are only allotted half a platoon even for the most important battles.
 * This also makes the game harder for some factions. For example, the standard infantry doctrine of the Imperial Guard is Death of a Thousand Cuts, as Guardsmen are too weak to fight melee. They need something to keep the enemy at bay to Beam Spam the enemy with their lasguns - the only thing they're good at is to Zerg Rush the enemy with ranged attacks. Ogryns assisted by a Priest are perfect for this task - but in Dark Crusade, Ogryns are capped at one squad at a time. If the entire enemy force is concentrating their fire on the Ogryns, the meatshield will be gone long before the Guardsmen can put a dent in their targets. This can be horribly jarring to players who got used to Winter Assault's capless units.
 * As a rule of thumb, every unit beside basic ones is capped. High-tier units (even ones that don't need relics) are usually limited to one at a time. This makes Assault Terminators nigh-useless as they die too quickly (since they're melee-only, they are always the ones at the front of the army and thus, the first ones targeted but they don't have enough HP/armor to take massed firepower).
 * In at least one level of said expansion's single player campaign, it is possible to circumvent these caps by exploiting the enemy's use of a weapon that puts units within its range in temporary stasis: once a player loses control of his units, they do not count towards his army total so long as they remain that way, and so further units may be built to "replace" them in that span of time.
 * The most impressive case of all, however, is the practice of building and killing as many Necron warrior units (in the same place) as the player can be bothered, and then using an upgrade for the commander to revive all of them (allowing armies of at least twice the pop cap). This is helped by the fact that a basic squad of warriors - 3 - costs nothing. Which was why they capped it in the next (and somewhat disregarded) expansion, Soulstorm.
 * One of the Game Breaking Bugs in Soulstorm is that, if an enemy Essence of the Deceiver briefly converts a player's capped squads to the Necron side, a fast enough affected player can build another of the affected squad type and retain use of it even after he regains control of the converted units.
 * This trope hits much harder for the Space Marines inside Dawn of War 2's multiplayer - you'll generally be able to have around 8 infantry squads for them, or more likely around 5 if they are upgraded with a sergeant. The standard squad size for the them is 3, potentially 4 if you get a sergeant. With a cap of 100 population with generally 5 for one Space Marine squad member, needless to say, you won't have many men out at one time. Other races may have around two or three times as many for their infantry squads at the same rough cost, however. The most infantry one may have at one time in the multiplayer is 98 Rippers for the Tyranids. But, Rippers are pretty much Redshirts, so don't expect much from such an army.
 * In the single player, you may have only 4 squads or units out at one time. On the other hand, they are Space Marines which at a point explicitly state that they recently suffered a horrendous defeat that depleted their chapter's manpower, so its arguably justified.
 * The general shortage of numbers perhaps but not the need to chose 4 units out of 6 for deployment.
 * In RHDE, only the first three beds per side attract units.

Strategy -- Turn Based

 * Final Fantasy Tactics, though listed partially as a Role Playing Game, does give the player the ability to hire new recruits, in addition to the plethora of warriors who are constantly joining your party. The game allows space only for a limited number of troops in one's party. On one hand, this makes sense, as it would be impractical for game space as well as time spent on training a large army of troops 4 or 5 at a time in battles (the allowed number per skirmishes). On the other hand, sending a dozen or so warriors against the ultimate evil does seem a little low on firepower, and makes one wonder if anyone truly cares about the state of the world. (See Apathetic Citizens.)
 * In Tactics Ogre in that respect: the player can form parties of ten soldiers, the only limitation being that only two L-class soldiers (such as Golems and Octopi) are permitted.
 * The Advance Wars series of turn based strategy games has an arbitrary cap on the number of units you can build (50), but it's high enough that it's very rare for anyone to actually reach it.
 * The unit cap is 60 in Super Famicom Wars.
 * Fire Emblem has a limited number of deployments per chapter. It changes each chapter as to how many troops can come with you. A few of these they will make a passing mention of how this is supposed to be a 'low key' attack or how only so many people can pass, or the others are guarding something. In general it's just to make it challenging, as Fire Emblem is Nintendo Hard. Although 9 and 10 try to justify it as a Vanguard. Averted in 4, where the player could field every unit (somewhat necessary, as the maps were HUGE, not to mention that the game had far fewer units to choose from than do the other games in the series).
 * Super Robot Wars follows the Fire Emblem model, and typically by the end of the game you'll have at least two or three times as many robots sitting on the sidelines as actually participating in a fight. The exceptions are the squad-based games, Alpha 2, Alpha 3 and Z, which group up to three or four robots into a single squad and then let you deploy of to 20 of those, allowing all or almost all the player's forces to participate in many battles.
 * Averted, or rather worked around, in Super Robot Wars W, where your ships could gain the ability to switch out active and reserve mecha during battle. The game also had the "Support Request" ability, which allowed characters to call in a reserve character for a supporting attack, as if they had been right next to them the whole time.
 * Averted in Mugen no Frontier. Out of seven units, only four can fight, but the other three can do Support Attacks, which can be helpful - maintaining comboes, finishing weakened enemies without wasting a turn, and increasing the Frontier gauge as a bonus.
 * The Total War series feature two such limits : the armies in the first two games couldn't have more than a given number of units (with the exception of crusades and jihads in Medieval, that could have 4 times the standard number, however only standard-number units could take part in battles at the same time, with the rest trickling in as reinforcements over the course of the battle when other units were killed off or routed off the map). The third and fourth game feature both this unit limit, but also a limit to how many individual soldiers can be in one army regardless of the unit count. To be fair, the soldier thing is more of a technical issue, and can be expanded by tweaking the game files.
 * In the Shining Force series of games you were restricted to the number of people in your ?army?. Thus you normally ended up with an army of twelve which the enemy army had well over 30. In game mechanics this made sense but in plot line when you?re about to fight the Big Bad it doesn't make a lot of sense not to use all your men.
 * Actually, there is a minor subversion in Shining Force III; a battle in scenario 1 had your force split into two. The primary group, whom you had been playing with all game and so were all ridiculously high levels took one force, leaving the secondary group filled with characters you used once and discarded to take on the roughly same size force in a separate battle that determined when the primary group could stop fighting an unkillable killing machine
 * Nippon Ichi games generally have limits: The Disgaea games limit you to ten on the field at once (though you can switch between them), and Phantom Brave limits you to 16 units, including weapons, and the characters also have an Arbitrary Time Limit (Ivore Island, Marona's home, has an Arbitrary Limit of 50 Things, whether that be items or Phantoms).
 * There is also an arbitrary limit on the amount of specialists you can put onto any given item in the Disgaea games. Though the sense of that limit feeling arbitrary is somewhat averted by the fact that the rarity of the item determines the limit.
 * Makai Kingdom allows a work around which then ends up running into a headcount limit anyway. You still have a limited number of characters on the field, but you can send in warehouses full of additional people, and then throw some of the foes into the warehouses to force them to try fighting all of the friendly people inside. These warehouses could have so many units that you could have situations where you had sheathed your weapon to pick someone up and couldn't take your weapon back out again because it would go over the limit to have the weapon displayed.
 * Soul Nomad and The World Eaters limits your number of units by "rooms"; each room holds a number of troops in a neat squad. The rooms are kept in a pocket dimension Gig created (with considerable ease, he claims) and the number of available rooms only increase by the progression of the plot, not any expenses made by you. Technically Gig should be able to give you all the rooms you need right away, although his being a card-carrying Jerkass might explain it. (And the fact that he'd much prefer if you just took his friendly offer to share his immense power... cue Bad End.)
 * In Luminous Arc, the character limit is 8 characters maximum in battle.
 * Luminous Arc 2 changed the limit to a maximum of 6 characters that can be deployed into any single battle, unless otherwise (generally at a smaller number).
 * Luminous Arc 3 followed the previous game with the 6 characters limit.
 * Ogre Battle allows you only ten units at a time, and each unit can have 5 characters, but a large character (dragons, monsters, golems, giants, or some demons) counts as two.
 * Tactics Ogre has perhaps one of the largest player parties outside of real time strategy games, at ten party members during battles. And when one includes any potential Guests adding to the roster, it can be even more. This leads to one battle early in the game where you just disgustingly outmatch the enemy, since you not only have your ten party members, but Kachua, Vice, and Leonard...against just little old Nybbas, two Mooks, and a couple undead that die easily.
 * Its Gaiden Game Knight Of Lodis also has a cap that exceeds the maximum battle limit, but this is likely because not only is it a strategy RPG, but there are two parts in the game in which you have to split up and attack from two sides at once.
 * In Cross Edge you get a rather large cast of playable characters from different games, but only four can be in battle at any time. Granted you can swap out characters (even dead ones) for other members of the in-active party, except for some plot battles that require certain party members to be in at all times, you are still only allowed four in the battle party.
 * Hogs of War never lets you control more than five pigs at once, with some missions in single-player and most multi-player battles limiting you to less than that. Multi-player deathmatches are interesting, as thanks to respawning you'll always have the maximum number of pigs - no more, no less.
 * Wild Arms XF allows a maximum of 8 units on any map, sometimes less. You can create as many Player Mooks as you want, though.

Survival Horror

 * Resident Evil Outbreak, both installments, only allowed four players to play together online, despite the fact that "Outbreak" (the first scenario) proves in the intro that all eight characters were together at the time. Offline it's even worse, as the player is only joined by two AI partners. A fourth occasionally shows up, but they exist only to be killed during gameplay.
 * In the original Corpse Party for the PC-98, there are five party members. Though they start out together, they're quickly split into a main party of three and a secondary party of two, the latter of which stays behind where they think they're safest, only to end up separated from the others, at which point they spend most of the game simply trying to get back together. Once they've finally reunited, it's time for the Final Boss -- the only fight in the game -- and the player must select which three survivors to bring into the battle.

Wide Open Sandbox

 * Grand Theft Auto: San Andreas. No matter how much the cut-scene emphasizes the importance of the current mission, if your respect level is low, your allies won't go with you.
 * You do get a huge amount of respect from doing the missions though, so you should have a more than big enough gang to help out.
 * In both Grand Theft Auto: San Andreas and Saints Row, you can only bring so many gang members along with you at a time (8 in GTA, 3 in Saint's Row). However, you can only fit so many into a car, and the NPC gangbangers in San Andreas didn't know how to drive. In Saint's Row 2 on the other hand, they'll hop into the nearest car and follow you, which sometimes may be a Police APC.

Web Comics

 * The inversion of this trope is parodied in this Eight Bit Theater strip.
 * Like every other RPG trope, the webcomic Adventurers! makes fun of this.

Real Life

 * Ancient Greek theatres had a limit of up to three actors on a stage at once. Much of this had to do with requiring plays that could be performed with a cast of only three main actors. (Or in some early Aeschylus works, two.)