Guest Star Party Member

Character who joins the party temporarily. If this happens early in the game, they'll be much more powerful than you. If you're lucky, maybe you can unequip a Disc One Nuke from them. But if you buy them equipment, beware of So Long and Thanks For All The Gear!

If you see them again, it will probably be as an enemy; however, if they join your party again, they will seem a heck of a lot weaker. Unfortunately, what removes them from your party may well be their getting killed after you've gotten used to having them around.

But that's not to say they have to all be killed. A Guest Star Party Member may be Exactly What It Says On the Tin...a guest star. They may actually just leave the party of their own accord, become a Secret Character or a Bonus Boss. They may also just be removed from the plot for other reasons, such as simply deciding that they're done or being incapacitated.

Another time, a Guest Star Party Member may leave the party or be killed, and actually be replaced with a permanent character who is either equal to or greater than them or sometimes less.

Despite there being little incentive to keep this character in your party for gaming reasons (lack of weapons sold for them, etc.) it's popular in gaming fandom to force these characters back into your party via cheat codes or Game Shark.

Compare with Crutch Character and Awesome but Temporary. Contrast And Now for Someone Completely Different, where an existing party member takes over as the viewpoint character temporarily.

Action Adventure

 * The Legend of Zelda a Link To T He Past has Zelda, and later a monkey and a maiden . Later, a treasure chest will inexplicably follow you around.
 * The Legend of Zelda Links Awakening has Bow-Wow, a ghost, Marin, and the Flying Rooster. Bow-Wow and the rooster are actually useful, Marin gives you some fun scenes, and the ghost...is just a Broken Bridge character that you have to get rid of to get into the next dungeon.
 * The Legend of Zelda Ocarina of Time has Princess Ruto with you for the whole third kid dungeon. She's more of a hinderance though, than help. She kind of plays this in her later adult self, and dungeon.
 * The Legend of Zelda Oracle Games has the three pets- you can get one to join you permanently, while the others will only appear in the quests in which they're introduced in each game.
 * The Legend of Zelda the Wind Waker has Medli and Makar, who are actually playable for one dungeon each. If a Game Boy Advance is connected to the Game Cube while you play, Tingle can join in too anytime.
 * The Legend of Zelda Majoras Mask also allowed you to take control of Kafei in the final part of his lengthy sidequest, and is used to move blocks onto switches while Link battles enemies.
 * The Legend of Zelda Phantom Hourglass has a young Goron that Link briefly joins forces with to overcome parts of a dungeon and the first half of the boss battle. The player controls one at a time and needs to switch between them as needed. The Goron can fight and destroy boulders, but obviously doesn't have the same arsenal of items as Link does.
 * The Legend of Zelda Spirit Tracks has a Phantom . Like earlier examples, you switch between Link and the Phantom.
 * in The Legend of Zelda Skyward Sword.
 * Curly in Cave Story, who accompanies you like an Attack Drone throughout Labyrinth M.
 * in Ghost Trick for
 * In Star Control 2, the Spathi can be recruited as allies by doing an optional quest. However they all leave after only a couple months. Fortunately, you do get to keep any Spathi ships you happened to build during that time.

Action Game

 * D&D video game Demon Stone has a chapter where you are required to exchange control of your least used character for special guest star Drizzt do'Urden, the dual-wielding drow ranger who defines melee badassery for many D&D players. Combined with a nerfing of weapon enhancements, a single-target super attack instead of a multi-target super, enemies that regenerate, and a few segments that even remove the ability to swap into control of your other characters in preference for just Drizzt, playing the super-badass drow just plain sucks.
 * Soul Calibur 3's adventure mode features many characters coming and going in your party. They should in theory start out stronger than characters you always have available, however due to leveling up by fighting (even if you lose) it makes more sense to just keep using your own characters.

First Person Shooter

 * Blacksite: Area 51 is a rare first-person shooter example of this, where  However, despite being an augmented super-soldier (who can soak a few hundred bullets in the final battle), when he's on your side he's physically indistinguishable from your other AI-controlled squad buddies.
 * In the PC version of Ghost Recon: Advanced Warfighter, the President of the United States himself carries a pistol and follows you around (very briefly) after you rescue him from rebel soldiers.
 * At one point in Jedi Outcast, Luke Skywalker himself fights alongside you
 * Zoey, Francis, and Louis in the finale of The Passing in Left 4 Dead 2 assists your team by sniping at zombies from a balcony and tossing you items in between waves of hordes. They're also ignored by the zombies so you don't have to worry about protecting them.

MMORP Gs

 * World of Warcraft has many Escort Mission quests where the NPC can actually fend for himself pretty well. The Wrath expansion also introduced several group quests where the player can call NPCs to help him if there aren't enough other players around to help with them. There is also a quest to free captive horde soldiers that will join forces with the rescuer for a while as thanks.
 * Lampshaded in quests involving Harrison Jones which states that you are either being escorted by him, or are supposed to simply stay out of the way while he does his thing.
 * A rare MMORPG Example fromShin Megami Tensei IMAGINE Online: Early on in the game, you complete a quest to heal your former mentor's wounded Cerberus. The Cerberus accompanies you for the next few acts, and can be summoned like a normal demon. However, it suffers from the "Wounded" attribute, slowing it's growth. At the end of Act 3, Snakeman takes Cerberus away to continue his treatment. You can later obtain a fully healed Cerberus as a gift from Snakeman after reaching level 30.
 * This is a recurring theme in Shin Megami Tensei. In both the first and second game, you can get Cerberus as a mini-Disc One Nuke (it avoids the level restriction too), although you lose them soon after they've had their use; later you can get them back permanently.
 * Guild Wars has henchmen who are implied to be working alongside the various players and heroes. None of the heroes "leave" per se, but there are some henchmen who do not follow you to later areas. Most of the time, they are available for the first couple of missions then when you get to the main dungeons and missions, stay behind. A few do decide to not stay behind, or actually go ahead and join in different areas.
 * And most of the Loads and Loads of Characters in the Guild Wars universe don't make the cut to Eye Of The North, despite being in your party when you take the quest that begins the main Eye of the North questlines.
 * Some quests have you amass a bunch of support characters who actually can fight very well, while others Leeroy or are noncombat.
 * With a few exceptions, the central five (Mhenlo, Eve, Cynn, Devona, Aiden) will always be available. But the biggest exception is in Factions where Mhenlo is a non-henchman NPC who has to be protected at all costs.
 * Kormir fits this trope to a T, acting as a Crutch Character of a sort before losing her sight and

Real Time Strategy

 * Pikmin 2 features the Bulbmin, who are immune to all environmental hazard but can only be used in the dungeon they are found in.

Roguelike

 * In Pokémon Mystery Dungeon: Explorers of Time/Darkness, you are joined on a mid-game dungeon run by, who is a huge asset to your team as you can simply stand back and let him do the fighting to conserve strength. And later, you are joined by a
 * In the main series, the fourth generation has something like this: in certain areas you'll team up with another trainer who double battles together with you until you get through the area (all of your wild encounters will suddenly start being doubles) and heals everyone at the end of each battle. They only ever have one or two mons.
 * Until you complete the main Pokemon League storyline and unlock the Battle Tower, in which any of these trainers that you met are unlocked as Partners for the Mix Battle challenges and have random Pokemon with them, including legendaries.

Role Playing Game

 * Final Fantasy IV has Fusoya, who sticks around for only a single dungeon near the end. Additionally, Kain and Rosa function this way when they first join the party (departing again fairly quickly). In general, the entire party gets well-shuffled over the course of the game; only a few (Rosa, Rydia, Tellah, and Edge out of 11 characters) stick with Cecil for more than three dungeons at a time.
 * Heck, Edge is the only party member who permanently joins when you first get him.
 * Edge and Cecil obviously. Though Cecil does change class and gets his level reset to 1.
 * In the GBA remake, as well as the Mobile and PSP versions (but not the DS version) most characters are available for the final dungeon and the bonus dungeons however, making Tellah and Fusoya the only real guests.
 * Phantasy Star IV is in the same boat - 5 slots, 11 characters - so naturally 6 of them end up as guests.
 * Final Fantasy IV the After Years, the sequel, follows the grand tradition of temporary party members. Most of them either do not gain experience, or have a lower level cap than the normal characters do:
 * A handful of permanent party members show up as Guests in other chapters; namely Cecil, Cid, and Rosa in Ceodore's Tale, and Palom, Rydia and Kain in Porom's Tale,.
 * In addition, Biggs and Wedge are guests for the first part of Ceodore's Tale, Player Mooks are available in certain chapters, the Elder of Mysidia joins for a single battle in Porom's Tale, and Fusoya appears in the Lunarian's Tale.
 * Aerith in Final Fantasy VII is an unusual example in that, by all appearances, she is a permanent character, up until she dies. Sephiroth also counts, though you never actually control him.
 * She gets everything that the other characters get, an Infinity+1 Sword, full set of Limit Breaks (Although most of the time you get these items she is already gone), and more Character Development then anyone else up to that point.
 * The same applies to  in Phantasy Star II.
 * Likewise,  in Final Fantasy V, though in this case everything learned by this character goes towards.
 * Seifer and Edea in Final Fantasy VIII. While Seifer is useful for low-level players at the start of the game, Edea's abilities and Limit Break is fairly useless by the time you get her.
 * Laguna, Kiros and Ward are a whole Guest Star Party.
 * Beatrix in Final Fantasy IX. She assists the party for a short while early on, and then a little later in a duo with Steiner for a segment that mainly exists so that Steiner can catch up. Though she's pretty powerful when she's playable, you can kill her off in the Steiner section so that Steiner gets even more experience from the ordeal.
 * Then there are Cinna, Blank and Marcus. Cinna joins for the first two fights of the game, and earns his spot for "Lowest Attack" "Lowest Defence" and generally "Crappiest Character." Blank also joins for the first few fights, leaves for a while, then comes back for the Plant Brain boss fight before getting turned to stone. Marcus is around for the same fights as Blank and Cinna, but he rejoins later when Dagger and Steiner split up from the main group. He's pretty much a Zidane clone, with slightly higher attack. In fact, all of them are.
 * Some of them however transfer their stats to permanent party members (Blank and Marcus transfer their stat gains to Amarant and Eiko respectively.) Leveling makes your later Party Members that much more powerful.
 * Final Fantasy VI has a slew of these:
 * Biggs and Wedge, the two Red Shirt soldiers who accompany you in the intro sequence. They die shortly into the game.
 * The 11 Moogles who join to help protect Terra. Subverted in that you can recruit one of them as an optional character later, and through a glitch, you can get another. (Like the above example, the Moogles are based on characters you get later; if you sequence break your way out of recruiting one of them, you get the Moogle back at a mandatory point later.)
 * Banon, who has a game-breaking healing ability.. Which is good, because the section of the game you get him for is an Escort Mission, and if he dies, it's an automatic Game Over.
 * The Ghosts in the Phantom Train, who are pretty useless other than their Possess ability. You can recruit several of them, and if you don't have Shadow in your party (see below), you can even have two of them at the same time.
 * General Leo, who you get to use for one battle.
 * And finally, we have Shadow, a rare Recurring Guest Star Party Member. He can be optionally recruited at three different points during the game, though for the first two, he has a random chance of leaving at the end of a battle. If you wait for him on the Floating Continent, he can be permanently recruited after the time skip, otherwise
 * Seymour in Final Fantasy X. He joins you for only one battle: . He even has an Overdrive of his own!
 * Final Fantasy XII has six: Reks, Amalia (who's actually Ashe), Basch, Vossler, Larsa and Reddas. Reks is the Decoy Protagonist for the prologue of the game who promptly bites it. Ashe and Basch join for the long haul later while Larsa stays as an important character in the game . This is even explicitly made a game mechanic (the guest party member is actually labelled "Guest" in the menu, doesn't count toward the party's Arbitrary Headcount Limit, cannot have their equipment altered, has no Licence Board entry, and cannot be ordered around in battle except in the international version). Balthier practically Lampshades the trope the first time it occurs, outright calling Amalia the party's "guest" and basically explaining all the above mechanics without quite breaking the fourth wall. There's also a plethora of friendly minor NPCs during certain Monster Hunts who your party will treat as temporary party members (which can be annoying when they start trying to buff a guy who's got Reflect).
 * And again in Final Fantasy XII Revenant Wings, with, and . The latter of these two characters joins your party again, and thankfully, there is never equipment to buy for the first character, so there's no thievery.
 * Final Fantasy II has a whole stream of guest party members. Rest assured that whoever joins your party and fills the fourth slot will eventually leave (except for ). In the GBA and PSP versions, some of them feature in a bonus section after the main game, complete with whatever equipment and magic they had when they left, making So Long and Thanks For All The Gear actually useful for once.
 * Note, however, that unless you powerleveled all of these characters in the main game, they will likely get murdered by the more powerful enemies.
 * Final Fantasy XIII has Gadot and Lebreau, Snow's lancers in his anarchy/resistance group. They fight with him in chapters 1 and 2 and function as Crutch Characters.
 * Lightning and Snow in Final Fantasy XIII-2. While Lightning is temporarily playable, Snow is a straight up guest.
 * Many worlds in the Kingdom Hearts series have a special party member that can swap in on that world only. They never need equipment (most don't need weapons or armor, the rest come with what they need), they leave if you exit their world, and they swap with one of your permanent party members (Donald Duck or Goofy). One wonders why the designers didn't just put in a fourth party slot, and leave it empty most of the time.
 * Probably because Square-Enix has mostly stuck with 3 character parties since Chrono Trigger.
 * A guest star party member actually plays a major role in Kingdom Hearts II.
 * Kingdom Hearts: 358/2 Days has practically only this in the story mode. Roxas either fights alone, or with another Organization member specified by the mission. You have no control over them, aside from selecting one of three general behaviour options.
 * Kingdom Hearts: Birth By Sleep does the same thing, with the guest star party members being the other two keyblade masters you aren't playing as, Prince Philip, young Hercules, Zack, Experiment 626 and Mickey Mouse.
 * The Xenosaga trilogy has four of them. In Episode I, Lt. Virgil, the trigger-happy, misanthropic, Blood Knight in Sour Armour, joins the party for a very brief time (like an hour if you're progressing really slow) at the beginning of the game . Episode II takes a more unconventional route by having both the stone-faced Badass Realian, Canaan, and the dopey Unfazed Everyman of the series, Allen, be technical guest character without them making any actual contributions to the gameplay. This is accomplished by having them appear as "co-pilots" of two of the party's Humongous Mecha (Asher for Canaan, and Dinah for Allen). In Episode III, Canaan and Allen are actually playable, however, and are joined by the other Genius Ditz of the series, Miyuki (our protagonist Shion being the original one).
 * In Xenoblade Chronicles, Alvis, Dickson, and Mumkhar each fight in a grand total of one battle each as party members.
 * Teepo in Breath of Fire III leaves the party near the beginning of the game - whereupon everything he has on him is subject to So Long and Thanks For All The Gear. Luckily, skills he learnt from enemies beforehand are transferred to the skill note list instead.
 * Common in the Tales Series:
 * Chester in Tales of Phantasia. He rejoins much later in the game, but at the same level he was at when he left (which makes sense, because most of the game actually takes place in the past, so what was weeks and weeks of adventuring for the rest of the party was just a few minutes to him). Add that to the fact that he has no special attacks at all in the original SNES version and he's mostly useless by the time you get him back. The Playstation and Game Boy Advance remakes expanded his arsenal and contained added scenes which allowed Chester to get his levels back up to snuff relatively rapidly, making him even more Badass Normal.
 * Even in the original SNES game, He's not entirely useless when he returns, if you get his levels up, he can actually hit as hard as Cless just using his normal attacks.
 * Leon in Tales of Destiny.
 * Ras in Tales of Eternia.
 * Kratos in Tales of Symphonia. Twice.
 * In the sequel, Dawn of the New World, most of the party are partial examples in that they will leave and enter your party frequently (having up to four of them in your party at once until the later parts of the game; you finally get them all at once in the final chapter) but you can never change their equipment, you can't have one of them as your active member, their titles randomly change between one from the first game, and instead of gaining experience or leveling up they have a fixed level that changes depending on what point you're at in the story. Richter is a straight example.
 * Asch in Tales of the Abyss. A rather Guide Dang It glitch can be used to keep him in the party instead of the main character (who he replaces during his stint in the party), at the expense of a few treasures and sidequests. He has two stints, and manages to get massively depowered between them without a Good Is Dumb moment - he just has the same equipment at the end of the game that he had in the middle, and it turns out that a sword that was pretty damn good 20 hours into the game isn't so great when everybody else has gotten a twofold increase in attack power.
 * Unless of course, you cheat to take them off...
 * in Tales of Vesperia, who joins for a grand total of one battle.
 * In the PS 3 version, however, he joins at four points throughout the story (the fourth being the aforementioned one battle). Shortly afterwards, right before The Very Definitely Final Dungeon, he joins the party permanently.
 * Richard in Tales of Graces. In the remake, he becomes a proper party member for the f arc with a greatly expanded moveset, and can be utilized in battle in the main story with a narikiri doll.
 * In the anime RPG Inuyasha: The Secret of the Cursed Mask, Sesshomaru joins you for a brief stroll around a castle, until you reunite with your party inside. His high stats and powerful combat abilities make him functionally invincible against the much weaker enemies you encounter.
 * If you jump though a ton of hoops to raise his affection up he'll join the the female PC (But not the male) for the final battle and give you a special ending.
 * Nicolai in Shadow Hearts: Covenant. All the advertising for the game hid how Yuri would return, so the players were to believe that Karin and Nicolai would be the major characters. Unfortunately, some idiot decided to put Nicolai's actual identity and intentions in his profile.
 * The Director's Cut also added two other temporary party members, with a section where you play as Nicolai, Veronica, and Lenny for a dungeon or so. (Antagonists, but Lenny is seen as the lesser evil and unsurprisingly is the only survivor)
 * Fallout 1 had a quest for you to rescue Tandi, the daughter of Shady Sands' leader, from a nearby raider camp. The game places her as a party member for the purposes of returning her home, but nothing really prevents you from taking her along to other places.
 * Liberty Prime in Fallout 3, a Pre-War bipedal robotic superweapon armed with laser eyes, spouts hilarious jingoistic propaganda, and throws scaled down nuclear bombs like grenades. Also, he's technically a part of the environment, and is thus indestructible. Admittedly, you're basically his guest star party member at that point in the game, but it's still awesome.
 * You can actually consider just about every companion in Fallout 3 to be a guest star. Many of them will only join for a single quest (usually an escort mission), some of them will leave on their own if your karma shifts too far from their liking, and none of them will follow you into the DLC areas (with the exception of Broken Steel). Companions you find in the DLC areas can't be brought back to the Capital Wasteland either and some disappear permanently once their quest is completed.
 * Fallout New Vegas has this in the first two DLC, since you can't take them into the main game. Dead Money has Dean Domino, Christine, and Dog / God; Honest Hearts has Follows-Chalk, Waking Cloud, and.
 * Skies of Arcadia uses an unusual variation. There are three main characters, and three other party members that constantly duck in and out of the story, replacing one another in your fourth party slot. Only at The Very Definitely Final Dungeon can you actually choose which one goes with you.
 * The beginning of Earthbound had a number of guest party members, including the hero's dog, his next door neighbors Pokey and Picky, and a bee from the future, which was the only one who could do substantial damage to enemies. Picky would mostly miss the target, while Pokey would just cower in fear. Later, while playing as Jeff, one gets followed around by a gum-chewing monkey who's no use in combat. You'll also meet the huge and powerful golem Dungeon Man, who gets stuck in some trees shortly after you meet him, and Jeff's best friend Tony, who follows him around during the escape from the boarding school but never assists in combat.
 * It's worth noting that none of the "guest" party members in Earthbound are controllable by the player.
 * There are also the Flying Men in Magicant, which are useless as anything but a meatshield by that point in the game.
 * Mother 3 similarly has characters that follow you around like this in the first few chapters, however straighter examples are, who are the player controlled characters in two early chapters, but do not participate in most of the game.
 * The first area of Chapter 3 is probably the only time you enjoy Fassad's company: he does the most damage in the first area.
 * The first Mother game had Pippi, Teddy, and EVE - Pippi and Teddy were controllable, EVE wasn't. Funnily enough, Pippi has the same base stats as Teddy.
 * Trask in the opening tutorial of Star Wars: Knights of the Old Republic. To some extent, this also applies to.
 * The sequel has B-4D4, who you control for a brief sequence during a storyline quest after
 * Seth the archaeologist in Phantasy Star IV, who's actually pretty competent, with some nasty spells like Deathspell and Corrosion that certainly help with the Soldier's Temple on Motavia. However, he's a particularly blatant case of holding back his true skills considering Naturally, this only comes up when you're forced to fight him. He seemed so friendly for ...
 * It's not clear
 * Lunar: The Silver Star had three: Ghaleon, Laike, and Tempest. Laike has a stupid-high attack rating, while Ghaleon possesses an array of destructive magic that makes Alex's weapons look wimpy in comparison. There's a reason behind both of them, though: Tempest? He just shows up for one mission when all of the female party members fall unconscious, and is barely heard from again.
 * In the sequel, Lunar: Eternal Blue, aspects of this trope are seen in the heroine, Lucia, who is a party member for most of the game, but is not under the player's direct control. She starts out as a Crutch Character, but spends most of the game in a depowered state. Then, after leaving the party late in the game, she returns for an event battle at the very end.
 * A whole party of Guest star party members appear in the tutorial of Baldur's Gate game, and leave as soon as it's done. Xan and Branwen do the same in Baldur's Gate II, with being a more straight storyline example.
 * SaGa 3/Final Fantasy Legend III actually had a space in your party that was reserved specifically for your Guest Star Party Members. Myron acts as the Crutch Character and pretty much solos monsters for awhile. Lara then joins for only one boss battles, but she isn't that much more powerful than a well-leveled party member. The next two, Faye and Dion, are much more powerful, and you spend a noteworthy chunk of the game with either Faye or Dion in the party. (This sadly makes Agron much harder because by the time you fight him, you're used to having a 5th party member). The manual then outlines a final one named Borgin, but in reality he is actually a permanent addition to the party.
 * SaGa 2/Final Fantasy Legend II also had this with guest party members, to a lesser extent. Some may only be there for a dungeon or so, while others may only be there for one battle. One is actually rather worthless, as the manual itself will admit. Two can be considered Crutch Characters, and one can be considered an Eleventh-Hour Superpower who is strong enough to take on the other copy of the final boss by herself.
 * Final Fantasy Mystic Quest gives you a different guest party member for each of the regions of the world. Each one of them joins exactly twice.
 * Subverted in Dragon Quest VIII, in which your party is briefly joined by the contemptuous and utterly incapable Prince Charmles during fights with Argon lizards (evidently just enough to give him some marginal legitimate claim over the prize). He inflicts 1 point of damage (if he's lucky and doesn't miss), and then flees.
 * Dragon Quest IV: There are several guest characters follow you that are AI controlled in battles.
 * Dragon Quest V has Prince Harry join you and also have your father assist you in a few battles in the early half of the game. Bianca can technically be a guest member if you decide to
 * Utterly broken in Dragon Quest VII, where you periodically get guest party members for a dungeon or two, often including the boss of that dungeon. While you can't control the guest, they have literally infinite HP and MP, and often an infinite number of healing items- and the boss is just as likely to waste a turn attacking the guest as he is the player characters.
 * Parasite Eve 2 has Kyle, a detective of some sorts, join Aya's side in a few parts of the game. He only has 100HP but can take hits better than Aya can. He cannot be healed at all, so if he dies, Game Over.
 * In Arc Rise Fantasia, this trope shines. In.
 * There's even a section of the game where you temporarily play as
 * Another point to make is that you get two characters with a hefty amount of control of before they're brushed aside by the plot: Alf and . Alf gets better stats and Excel Acts than L'Arc, only to be outdone by his ability to summon Simmah the Rogress.  .   on the other hand
 * In the Wiiware title Pokemon Rumble, the premise of the game is that the Pokemon are merely toys and cannot level up. Which means that you'll wind up selling your favorite Pokemon after about two levels.
 * The main series Pokémon games often have the player character teaming up with an NPC and their Mon, usually in a dungeon. They're lost and you have to lead them out. Somehow, though, you still do most of the battling even though their mon helps you out. In one or two cases, the NPC rewards you afterward. The annoying thing: No using H Ms while they're with you. So, no Surf,Fly,Dig, ect.
 * In the obscure but high quality Sega Genesis RPG Traysia, soon after starting the game the main character acquires a party of three followers who will follow him through trials and tribulations for the rest of the game. Well, all except the fourth party member,
 * Eternal Sonata had Claves, who joined for a dungeon before . You can get her to rejoin for the last boss, however, by completing the Bonus Dungeon.
 * In Song Summoner: The Unsung Heroes for the iPod, you rescue 'Superstars', platinum ranked party members with only 2 deployment. (Deployment goes down every time you use a party member in battle, more if (s)he gets defeated. Zero deployment and you lose the party member FOREVER.) On top of this, YOU CAN'T GIVE THEM REWIND! (+1 Deployment)
 * Jenkins in Mass Effect 1 kinda fits this trope, but all you can do with him is talk to him on the Normandy. Once you land on Eden Prime, he dies almost immediately. You can even assign him skill points, but they're useless since he dies before he gets to fire a shot.
 * Mass Effect 2 gives us Wilson, the chief medical tech in charge of . He accompanies you for part of the tutorial mission before.
 * The "Lair of the Shadow Broker" DLC makes Liara a longer-lasting guest star since she accompanies you for two levels. Unlike other guest party members, she has her own skill tree which you can put points into, and upon beating the mission you can even learn to use her Stasis ability as a bonus power, a la squad loyalty skills.
 * And then in the "Arrival" DLC, Dr. Amanda Kenson helps Shepard after (s)he busts her out,.
 * Continuing the tradition, Shepard's former CO David Anderson is a party member during the introduction of Mass Effect 3.
 * In Sonic Chronicles, Eggman joins the party for a while, and is capable of one-shotting robots if Tails is in the party as well. He breaks off near the second half of the game to make sure you can get back.
 * The Elder Scrolls games are notorious for their bad "out-of-the-box" ally implementations.
 * The earliest games - Daggerfall, etc. - featured any NPC who was with you as a face in the upper corner of your screen and they did not assist you in fighting or get hurt or die. Except for one egregious quest.
 * In Morrowind, having a "party member" meant that the NPC had the "follow" variable set but the only commands that were available were "Wait here a second" and "Follow me." If that unarmed unarmored low-level peasant you recruited happened to see a mighty Daedroth, he would run off to do battle without a second thought and probably perish in two swipes.
 * In Oblivion, the most plot-important characters are unable to die. Some of them even join you for a while as followers. There are few tricks to give them strong equipment, turning them into useful party members.
 * The first Gothic features a variety of individual quest allies who fight alongside you but otherwise pretty much do whatever they want. Notably, you are helped more frequently by Diego and Gorn.
 * And then there's Mud.
 * Legend of Dragoon had two, Lavitz and Shana. Similar to the above, when they leave they are instantly replaced with an equivalent party member. Albert may be arguably greater than Lavitz due to joining early and having more time for Character development, while Miranda was practically an Ass Pull and was thrown in to simply replace Shana so she could fulfill plot purposes, and for the possibility that someone actually did use Shana religiously. (Shana and Miranda are a mixed bag - some players will insist they're underrated, while others will say they're both worthless and Meru can do anything they can)
 * Counts for any party member you decide to sacrifice in the Valkyrie Profile games, with a few exceptions. (They become playable near the end of the first but by then, they're too far behind to be of any use to you) Due to Covenant of the Plume's strategy elements, there are literal guest members who sometimes leave but most of the time join at the end of the chapter.
 * Ancel deserves a special mention. He is a guest in the beginning but is sacrificed. In the A ending, he joins as a guest for the final battle.
 * Baldurs Gate party NPCs can be swapped in and out pretty much at will, but Shadows of Amn has  There are cheats to spawn him back into the party, but he can't level up past a certain point, and there are other NPCs of his class, so it's not really worth it.
 * There's also a point in Shadows of Amn where, during a side quest near the end, you meet Drizzt Do'Urden and his companions. Successfully negotiating the conversation will allow him to join you as a non-controllable NPC ally for one specific boss battle. (That same encounter can also include allies from the Shadow Thieves and the Order of the Radiant Heart, depending on your class and which quests you've done.)
 * Persona 3 has Shinjiro Aragaki. You lose him
 * Potentially averted in Persona 3 Portable:.
 * Sagacious Zu of Jade Empire is a strong character, but
 * Abbot Song from the same game. He joins the player after
 * There are several of these in Lord of the Rings The Third Age, including Aragorn (twice), Legolas, Gimli, Gandalf (twice), Eowyn, and some random Elf guy (multiple times). Each of them joins your team for a single battle or a series of consecutive battles, then leaves immediately afterward without so much as saying goodbye. I guess they have more important things to do than hang around with the main party of Fellowship knockoffs.
 * In Dragon Age: Origins, the Warden will have a partner or two during their origin story, before they start to meet their actual party-to-be: Eleanor for the Human Noble, Jowan and Lily for the Mage, Soris for the City Elf, Tamlen and later Merrill for the Dalish Elf, Leske for the Dwarven Commoner, and Gorim for the Dwarven Noble. It's not even over once they reach Ostagar: there's Daveth and Ser Jory, your fellow Warden recruits, and then finally a pair of anonymous Redshirts made available for the run up the Tower of Ishal.
 * The Addon Awakening gives you another one in the form of.
 * Dragon Age II has Carver and Bethany, though which one sticks around longer depends on Hawke's class (if Hawke's a Warrior/Rogue, Carver is killed, while Bethany dies if Hawke's a Mage). The surviving sibling will either die or be Put On a Bus by the end of the first act depending on your actions (though they'll return for the final act if still alive). The Mark of the Assassin DLC had Tallis, who's only around for the DLC.
 * The first Golden Sun game has Jenna join the party early on, but she after the first dungeon. She only becomes fully playable in the second game. When you know it's coming you can easily take her stuff, but her One-Piece Dress isn't going to do your now all-male party any good. The most she can steal at that point is a few herbs and some wimpy armor, anyway.
 * The third game, Dark Dawn, has Isaac and Garet tag along for the first dungeon, though they aren't directly controllable.
 * Kai in Po Po Lo Crois. Just about everyone if you don't do the sidequests to get 'em, since it's pretty much a revolving door of party members in the game.
 * Infinite Space has several, whether as a ship that temporarily joins your fleet or as temporary crew members (in which three of them become permanent members later), most notably Cico's Rudianos in Act 1 and both Dietrich and Nele in Act 2.
 * Quite a few characters from Star Ocean the Second Story could be considered this because they join your party before you decide whether or not you want to keep them, and you can choose not to recruit any character that could join your party besides whatever character you didn't choose to play as.
 * Leon probably best fits this trope as he joins you temporarily no matter who you're playing as, but can only be recruited for good if Claude is your player character.
 * After you meet up with Ernest (you have to have Opera in your party first) you can choose to let them both go.
 * The Might and Magic series had this featured in some quests where you would have to rescue a maiden or a child and they would tag along until you brought him/her to the person who told you to rescue the maiden/child. Another example is that almost every NPC in the could join your group and provide some sort of benefit while they are with you, sometimes, however, some people will join and do nothing at all except eat your food
 * Vampire: The Masquerade Redemption has this twice, once in the Dark Ages Era and once later in the modern era. In both cases, the Guest Star Party Member becomes an enemy, and in both it's a case of So Long and Thanks For All The Gear.
 * The last two missions of Eien no Aselia are built around Yuuto getting a powerup along with his girlfriend. However, Lesteena has no combat ability whatsoever. So instead, you get to use the white spirit Io, who has some pretty powerful abilities.
 * Diablo III does this with all your companions before you have the option of having them join you for real. Other NPCs also join you from time to time, such as Leah, and.
 * Diablo III does this with all your companions before you have the option of having them join you for real. Other NPCs also join you from time to time, such as Leah, and.

Survival Horror

 * A few survival horror games, while not having a proper "party" do temporarily switch control from your main character to a secondary one. Frequently, this is explicitly so the secondary character can save the primary one who is in imminent danger. Examples include Rebecca from the first Resident Evil and Kaede from the first Onimusha. In a subversion of a few of the RPG examples above, these guests are usually lacking in weapons and armor (Rebecca only has a handgun with no extra ammo) and can be a pain to play as.

Turn Based Strategy

 * In Disgaea 3, Master Big Star and Salvatore join the group for the final battles, and stay until you beat the last boss. They rejoin permanently soon after in the first two post-story events, though.
 * In Final Fantasy Tactics, there are often temporary members who assist your team in battle. If they accompany your team for multiple battles, they will even show up in your party menus, and you can meddle with their equipment freely. This is even occasionally true of a plot-important character that does not show up in more than one battle, such as Alma or Princess Ovelia, who remains with the team for an extended period but prefers not to fight. However, unlike most Guest Star Party Member situations, these characters will not be under your control during battle. They will be labeled Guest, to distinguish them from the ones labeled Enemy, but both guests and enemies are computer-controlled. Enemies that are subjected to a successful Invite attempt by one of your Talk Skill users will qualify as a Guest until the battle is won, at which point you will have the option of making them team members or turning them away -- they are not allowed to continue being a Guest beyond the initial battle. Guest characters are the only ones exempt from the "three turns KO'ed=crystal or chest" rule, primarily because of their importance to the plot. Once their role in the story is fulfilled, they can be recruited and at which point they can die for real at any time after that.
 * One interesting example is Gafgarion..
 * You also fight two battles with a permanently dead guest character.
 * Interestingly enough, the first time you meet Boco the Chocobo, he's a Guest for the Enemy. (This was probably done so that Boco can't be turned into a Crystal or Invited into your party.)
 * Final Fantasy Tactics Advance also had guest party members, but unlike the Playstation version, the guests here only aided you in the battle they appeared in and they never join the party afterward, nor can you fiddle with their items.
 * Final Fantasy Tactics a 2 has guest units again, but this time by the buttload and several are an Escort Mission. There's even a few occasions where monsters are counted as guests! Some missions even has a few boss characters joining you in a few battles.
 * Common in Super Robot Wars, though not so often at the beginning - instead, you are able to recruit a boss enemy, and their stats are often downgraded to party member level when they join. Sometimes, however, they keep full power until the next mission, which gives you the fun situation of having a character with 90,000 HP on the field.
 * Similar to the Final Fantasy Tactics example above, you are frequently given ally NPCs in said games, who tag along with you, mostly good-for-nothing redshirts, but occasionally someone will show up who's actually useful to you. Examples that come to mind are  in Original Generation 2, whose arrival is much-needed, as you're fighting a near-final boss level character, your only character currently able to fight happens to be so badly damaged that doing anything with him other than just surviving is sheer suicide, and you can't send any reinforcements for several turns. Also from the same game, , who you defeated earlier and shows up to help fight against Wendolo. Unfortunately, he's defeated by a scripted plot event when Wendolo's mech's HP reaches 1/3rd of its max, and since he shows up when said mech is down to 2/3rds of its max HP, he effectively is only around for a third of the battle, and this editor never got to use him.
 * The Barcoff Squadron and Gregor, Baiman and Muza in Scenario 39 of Super Robot Wars Z 2.
 * The Fire Emblem series has tons of these, but the most extreme example would be
 * Not quite as extreme as you think; Shinon and Gatrie are also this in the beginning of 9, although both rejoin you mid (Gatrie) to late (Shinon) game. A good chunk of 10 takes this trope to its logical conclusion; the parties remain the same, it's the player who keeps guest-starring on opposite sides.
 * In the same vein as the black knight are the laguz royalty--Tibarn, Neasala, and Cainghis (and his loyal aide), who join only at the very end. Athos in 7 does this as well, as does Gotoh. Many times they do this to give characters with low-level parties a chance at beating the final boss.
 * Shinon and Gatrie rejoin you IF you can work out the secret hidden order of people who need to talk to them. Gatrie's not too bad on this, but Shinon is a nightmare, and great at getting himself killed before he can complete his Face Heel Face Turn.
 * The Fire Emblem series also has, who shows up in one Gaiden chapter before undergoing a Face Heel Turn in his first appearance in the main story and showing up eight chapters later as a boss. He's a Crutch Character, so most people wouldn't really use him anyway, and he has good equipment. Which should of course be taken away immediately to keep him from counterattacking enemies, turning him into a nice little meat shield for his one appearance who, of course, you don't care about since if he's defeated, he'll just show up as an enemy again anyway. And you can get him in back in your party post-game.
 * In another example of a Guest Star Party Member being succeeded by an identical party member, Ninian and Nils, the Not-So-Spoony Bard characters in Fire emblem 7. In the prologue, nils the bard joins. Then during the main game, Ninian joins but then leaves. At the very end, Nils rejoins again with Ninan's stats. (Because they are Not as spoony as most Spoony Bard characters are. Sure they are defenseless but they can buff and allow units to move again, which is extremely powerful in a turn-based strategy game.)
 * Jeanne D Arc for the PSP has several characters who join and then leave, but come back but the biggest example is But the second the longtime Guest Star Party Member leaves, another identical party member replaces them.
 * Tactics Ogre has numerous guest star characters; due to branching storylines, some characters will just be guests on one path, whereas on another path they will be permanent additions to your army.
 * Lans, Warren, and Leonard are perhaps the best examples of this in Tactics Ogre, since nearly every Guest Star Party Member is either recruited or killed in one path except them. Or you can make everyone be a Guest Star Party Member by rejecting them when they offer to join.
 * They are also the examples of when the trope overlaps with Crutch Character, as they do most if not all of the work for you when you have them on the map.
 * The pseudo-prequel Gaiden Knight of Lodis also has this, and the only true guest characters are Justin and Lara, later found as enemies. (You don't have to kill them as the only stage they appear on is a Defeat The Leader stage.) Rictor and Orson are guests only in the "A" path, Cybil is a guest only in the "B" path, Eleanor and Ivanna ask to join regardless. (Shiven does not serve as a guest, being a spy)
 * In Shining in The Darkness, if you rescue Gila, he joins the party as a non-player-controlled character who occasionally participates in battles, but leaves the party when they next spend a night at the Tavern.

Turn Based Tactics

 * Odium has three permanent characters, as well as two other slots which keep changing as various allies join, depart or are killed off. You begin with the three guys, and by the final level of the game you're back to just these three again.

Anime and Manga

 * Nefertari Vivi of One Piece fits the bill. While she never officially joins Luffy's crew, she sticks around with them for a couple of story arcs after her introduction and becomes a major character during that time.
 * Similarly, Jinbe for the Fishman Island arc.

Web Comics

 * In RPG World, the group fights Galgarion at one point, with (former) Evil Soldier #347 joining them as a "computer-controlled" ally for the battle after Galgarion.
 * In The Order of the Stick, Celia plays this role for Haley and Belkar after the party splits. She can't help them much, though, as she's an Actual Pacifist.