Hold the Line

[[caption-width-right:305:"The Thin Red Line", by Robert Gibb

""Before the network, there was the fleet. Before diplomacy, there were soldiers! Our influence stopped the rachni. But, before that, we held the line. Our influence stopped the krogan. But, before that, we held the line! Our influence will stop Saren. In the battle today, WE. WILL HOLD. THE LINE!""

- Captain Kirrahe, Mass Effect

A Hold the Line mission is a type of Timed Mission, where instead of completing a mission in a set time, you have to prevent the enemy completing their objective before the time runs out. This usually means you are defending your base, or a certain character, until reinforcements arrive, or vital repairs are carried out on the base. Sometimes the enemy is an overwhelming force, so actually defeating the enemy, or even surviving much beyond the time limit, would be impossible, without reinforcements or similar. Fortunately for you, victory will usually occur instantly and automatically as soon as the time runs out, even if you were moments away from defeat.

This is common in Real Time Strategy, where success usually required a balance between creating defensive structures and units to protect your objective, and scouting out and eliminating enemy bases to reduce their number. It also crops up in First Person Shooter games, most commonly as an objective-based multiplayer gametype.

Sometimes it might be linked to an Escort Mission, where you have to escort someone to a location, and then protect them while they (for example), hack into the enemy's computer system.

In multiplayer, this mode of gameplay also exists, usually with the teams switching after the attackers win or the timer runs out. In many cases, there are several lines, and the defining criteria (if neither team manages to break through them all) are usually which team got further or which team got to the same line first. Naturally this can result in tie games. Strategy games of all kinds love this trope -- there are very very few that do not have an example of a Hold the Line mission.

When the "objective" is to kill the enemies, you got yourself a Multi Mook Melee.

Fictionally, often a form of You Shall Not Pass or Last Stand.

Protection Mission is this combined with defending a stationary object. Compare The Siege.

Action Adventure

 * Happens some levels of Soul Calibur Legends, where you're allies hold the line to give you time to kill a dragon, liberate a castle or just get to their position to help.
 * The Legend of Zelda Majoras Mask has an optional mission that requires you to protect a barn against a bunch of otherworldly creatures until the sun rises. You cannot use your sword to defeat them, so you have to be skilled with your bow to succeed. A mission that occurs after that requires you to protect milk jars from a pair of muggers while riding on a covered wagon. If you manage to complete both missions you are rewarded with Romani's Mask.
 * The final boss of An Untitled Story, after defeating his fourth form, becomes invincible and the only option is to avoid his attacks until the timer runs out.

Action Game

 * Battle City series by Namco is also an early example where player(s) have to defend the base in addition to keep themselves alive. The destruction of the base results an instant game over.

Beat Em Up

 * The Konami-Slasher OZ Over Zenith (known in Europe as Sword of Etheria) has you defending your pillars as the corners of a (fictive) square, which means you have some running around to do. At least one pillar has to be left standing, which is a lot harder than it sounds, since monsters are about everywhere.

Fighting Game

 * There are many such missions in the Magical Battle Arena Lyrical Pack. The first one which unlocks Hayate isn't too bad since you can take out your enemies. The later ones however, has you trying to survive against multiple, invincible copies of a character that are permanently in Super Mode and firing Limit Breaks like there's no tomorrow.
 * Some of the Event matches in Super Smash Bros Brawl have conditions in this style (for instance, Olimar having to keep his Pikmin alive until they blossom).

First Person Shooter

 * Defending Natalya as she hacks the Control Room computers in GoldenEye. On higher difficulties, this can be more challenging than the Final Boss.
 * Half-Life 2 does this from time to time, with the player needing to protect Alyx (who is thankfully rather durable) as she completed some task or other. In Half-Life 2: Episode One, the developer's commentary at one point says that they specifically didn't include this sort of situation, because it just looked "robotic" to have her either just sit there and take the abuse from the Combine or zombies, or stop what she was doing to fight back and then start all over again.
 * ...but then they make a similar scenario into the final boss fight for Half-Life 2: Episode Two.
 * Indeed, in Episode One this occurs the other way round, with Alyx defending you.
 * More importantly, the entire series is rife with elevators and teleporters that the player has to defend himself while waiting for.
 * Any HL2 player's hatred for the pesky turret guns that fall over if you look at them wrong will be raised to the power of itself after the level in Nova Prospekt where they are hacked to be on your side and need to be used to keep the baddies at bay. The hacking does not improve their stability.
 * The game Call of Duty 4, includes a mission called "One Shot, One Kill." You and a wounded partner attempt to defend a landing zone next to the famous ferris wheel near Chernobyl.
 * Another example later in the same game as the player's squad running a small retreat action to hold a landing zone for extraction, hitting the seemingly infinite enemy forces as they fall back. After taking out four tanks (not bad for a special ops squad of six), they are then told that the LZ has been moved...to the area they've just let the enemy overrun, forcing the squad to go from Hold the Line to Attack The Line, breaking through the enemy's heavy defenses to make it to the LZ. May also be considered the Scrappy Level.
 * In fact, there isn't a game in the Call of Duty series without at least a couple spots where you have to stop advancing and defend a position. Many of these follow a pattern: Get to the place you're defending, survive the infantry attacks until the enemies deploy armor and/or heavy weapons, then destroy the heavies to win the battle.
 * Or, in the case of levels like Loose Ends, get the hell out.
 * Call of Duty 2, in addition to a level actually called "Hold The Line", includes "Comrade Sniper", the second half of "The Silo", and "The Battle For Hill 400" (the crowning level of awesome).
 * Call of Duty 1, had two shining examples of these, but they were both pretty hard. One was Pegasus Day, holding the bridge you'd taken the night before, using a fixed gun emplacement to rout enemy tanks. The second was the ever frustrating Pavlov's House mission.
 * 2 had so many of these that you'll probably shriek "AGAIN?!" whenever that objective comes up.
 * Similarly, the Medal of Honor series is loaded with these kinds of objectives, such as defending the house in MOHAA's "Battle in the Bocage"(which is called back to in Call of Duty 2's D-Day mission), "The Bridge", which is also a Sniping Mission and Escort Mission, and the penultimate battle of MoHAA: Spearhead. In some levels you have to "Break the Line".
 * The new Medal of Honor game has a fairly epic one where you and three other rangers defend a "house" (loosely used, since its more of a shell) that gradually gets more and more destroyed as time goes on until you are pretty much sitting in the open with mooks coming at you from all sides.
 * Halo multiplayer has a bunch of these for their objective games; notably Capture the Flag, Assault, which involves one team trying to bomb the other, and Land Grab/Territories, which fits this trope to a tee as it involves holding parts of the map to stop the other team from capturing it.
 * The single player campaigns have several examples of this too, for example, parts of the second mission of Combat Evolved, and the last part of "Sacred Icon" in 2.
 * Team Fortress 2 on Payload and Attack/Defend style Control Point maps, this is the Red team's only job--in fact, you can earn achievements for accomplishing total shutouts in Gravel and Dustbowl. Blu, on the other hand...
 * Each of the finales from the Campaign mode of Left 4 Dead involves one of these situations, wherein the Survivors must fend of literally hundreds of Horde and dozens of Special Zombies until some form of evac arrives.
 * Specifically, it's two Hordes and two Tanks, alternately.
 * And then Valve added Survival Mode, where the rescue vehicle never comes. Oh, and the Tanks and Horde don't wait for each other. The Tanks also start showing up in teams. It's the longest (final) ten minutes of your life.
 * In Frontlines Fuel of War, the game ends on one of these. You just seized control of the Russian Ministries of Information and Defense, and now you're in what must be Red Square. You, along with a handful of fellow Western Coalition soldiers, must hold out against a massive Red Star counter attack.
 * This is Halo 3 ODST's Firefight mode in a nutshell. 5 waves of enemies in a round, 3 rounds in a set, infinite sets in a game. Of course, they also activate skulls as you complete rounds and sets. Getting one of the seven Vidmaster achievements (you need all seven to unlock the Recon armor for multiplayer matches in Halo 3) requires a four player team to finish the fourth set on Heroic difficulty (which is easier than the first version, which required getting though the seventh set on Legendary. Good thing it was changed before release). A Firefight game ends in one of two ways: Everybody leaves, or everybody dies (or someone without a 360 hard drive, which is needed to play co-op, joins the game and causes it to abort).
 * Similarly, the epilogue of Halo Reach. Failure Is the Only Option.
 * Bio Shock 2 has this as a recurrent feature: defend a Little Sister against waves of Splicers until she's done harvesting
 * There was at least one mission in the original Bio Shock where you had to defend a location without moving. One example is the lab defense level, where you're warned by Atlas of an oncoming assault, and you're forced to fortify your position.
 * Part of the Assault gametype in both Unreal Tournament and Unreal Tournament 2004, which re-enacts a 'historic' battle, and each team trades off attacking and defending sides. The first attacking team can get a serious advantage if performing well in their round, as defenders they only have to hold the line for the amount of time their victory took.
 * In 2004 and UT3, holding the line is a good Onslaught tactic for the side that already has the points to win. A team with control of a Leviathan, and a coordinated defense, can simply count frags until the clock runs out.
 * At the end of Soldier of Fortune's fifth mission, you have to hold the line while Hawk disarms the Lightfoot nuke. A Luck Based Mission on the Challenging and Unfair difficulties, about as nasty as the Control mission in GoldenEye. Sometimes the enemies stop spawning prematurely(you have to kill a set number for the mission to end), making the level Unwinnable.
 * In Metroid Prime 3, there is a section where Samus must protect a portion of Skytown from Space Pirates until it's able to drop a bomb on a Leviathan Shield. Interesting in that while Samus is protecting the bomb, the Space Pirates are trying to protect something from Samus.
 * The end of the Island Estate mission in Rainbow Six 3. Given that you die very quickly(it's Rainbow Six no less) and there's very little cover, there's bound to be much frustration.
 * Doom 3 often did this with swarms of literal Demonic Spiders (Trites and Ticks), such as when waiting for a ladder to drop down.
 * In Star Wars: Battlefront II, there are missions where defense of a post is necessary: one mission in particular is on Kashyyyk, where the Republic clone army must defend an oil refinery from the Confederate droid army while waiting on Jedi Master Yoda to come with backup.

Light Gun Game

 * A number of stages in the Point Blank series have you keeping enemies away from Dr. Dan and Dr. Don until time runs out; failure results in the stage ending with one life lost.

MMORPG

 * Much like its RTS predecessor, World of Warcraft also features this type of encounter. The time-travel dungeon Black Morass and the magic prison known as the Violet Hold both are Hold the Line missions, while other dungeons have segments that work this way. Not to forget the latest Pv P additions, Strand of the Ancients and Lake Wintergrasp. In both cases, one side defends a keep against the other, but the previous one is played in two rounds, swapping the roles much like in the FPS mode it's rather obviously inspired by.
 * Guild Wars loves this trope both in missions and challenges. Two that immediately spring to mind are the Factions mission "Arborstone" where the player must defend a character who is casting a spell to open a door, and the Prophecies mission "Sanctum Cay", where players must hold off waves of bad guys on a beach as a mage stands on a pier summoning a magical ship so that the party can escape.
 * Monster Hunter goes in this direction when you fight certain gigantic monsters, namely the huge crab Shen Gaoren, and the even bigger dragon Lao-Shan Lung. Instead of hunting them like you do with other monsters, the creature shows up at one end of a linear area, and past multiple obstacles is a fort on the other end of the map. You have to prevent it from destroying the fort, by either killing it before the timer runs out, or repelling it by dealing enough damage that when the timer hits 0, it flees. If you run out of time before damaging the monster enough, get knocked out three times, or let the fort get destroyed, you lose.
 * The Jhen Mohran fight in Tri is a two-parter. The first involves chasing and causing whatever damage you can to it on your Dragonship, and the second is this trope. Again, if you clock out before hitting the "repel" damage threshold, you expire your faint tally, or the Dragonship is destroyed, you fail. It's possible, however unlikely, that the Dragonship will be wrecked on the first phase; hope your team isn't that sloppy.

Party Game

 * A good part of the Wario Ware microgames involve preventing something from happening, as opposed to accomplishing a task yourself. For instance, one microgame simply requires you to prevent pinballs from falling bellow the gutter.

Platform Game

 * Mega Man Zero 2 has one of these. Zero must keep enemies off Ciel for 90 seconds so she can defuse a bomb.

Puzzle Game

 * In Tetris the Grand Master 2, fulfilling a series of obscure and very, VERY difficult conditions results in the "M-roll," in which you continue playing the game during the credits, but pieces become invisible on locking down. This lasts for one minute, and failure to survive results in the "M" grade, while surviving it awards you the "Grand Master" grade.
 * Klax has levels where the goal is to survive through a set number of tiles.

Real Time Strategy

 * War Craft III invokes this trope four five times during the "Reign Of Chaos" campaign missions. The first time against an upset sea witch in the extended version of the tutorial. The 5th Alliance mission has defending a town for 30 minutes against the Undead until your allies arrive. The last Undead mission has you defending Kel'Thuzad for 30 minutes as he completes a ritual to summon Archimonde and the Burning Legion. The final Night Elf mission pits you and your allies against the Burning Legion for 45 minutes to let Malfurion complete his Deus Ex Machina. The Orcs had to hold the line against a horde of Murlocks while their ships were being fixed.
 * Some fan maps are centered about this trope, often with two teams of players trying to hold out as long as possible while trying to sabotage the other teams efforts (and in some cases, summoning the enemies). One lesser known map of this type goes by the exact name of this trope.
 * The secret mission in The Frozen Throne involves a Tower Defense mini-game where you hold off up to forty-five waves of increasingly dangerous enemies with increasingly powerful towers; if you succeed, you get a special bonus hero in the next mission.
 * The first Scourge mission in The Frozen Throne uses an inversion of the trope. You are keeping your opponents from escaping while you hunt down and destroy their bases of operation. If twenty or more humans escape, you lose.
 * Another inversion is in the second-to-last Night Elf mission in The Frozen Throne, where the Naga try to hold the line for 30 minutes until Illidan's spell is completed, and your task is to break the line and thwart them.
 * And it's even apparent in cutscenes. In the Frozen Throne Night Elf escort mission, Tyrande attempted to hold the bridge against the Undead forces using her Ultimate, only to have the said bridge collapse..
 * She did hold the line, in all honesty. She actually collapses the bridge intentionally in the end, just to ensure that the undead didn't reach the other side
 * She is next seen fighting back the Undead with her warriors. Why didn't she send runners or a magical S.O.S so she can be recued? And where did she find those warriors to help her?
 * The fifth mission of Grim Grimoire requires you to stay alive for 20 minutes against Imps and Skullmages while the others escape. Succeeding in this, however, triggers the Groundhog Day Loop portion of the storyline, and you're back to Day One. Also later in the game, you must stay alive for 30 minutes (on two occasions) while summoning the devil, Grimlet.
 * Mind you, you can win these scenarios by destroying all enemy runes, but good lucky pulling that off on the higher difficulty levels.
 * Several randomly-selected missions for conquering unoccupied territories in the Rise of Nations map campaign, as well as the first mission of the Napoleon campaign in the expansion, require defending a base (or several) against the barbarians/Royalist insurgents.
 * Starcraft had you defend a Terran base against a Zerg rush as the third mission. Being the third mission, your opponent isn't as well defended as they (and, perhaps, Blizzard) would have liked, and a good player can wipe them off the map before the time runs out, instead of defending.
 * Some lines removed from the final version suggested that was the intention.
 * The third mission in Starcraft 2 is basically the exact same battle being fought over the same ground. Wiping out the Zerg bases nets you achievement points.
 * A part of one of the later Zerg missions fits this trope, holding off a Protoss attack as you harvest from the Khaydarin Crystal Formation. The crystal formation is in the middle of three different Protoss tribes, each fully equipped with Carriers, Reavers and High Templars. You have to hold your base at the formation for ten minutes.
 * The final mission in Brood War's Protoss campaign is a version of this: you have to get your two hero units to a structure, then they go inside it, then you have to defend that structure until the task is complete.
 * Age of Mythology has a few. The first mission of the main campaign involves holding off the pirates until the main army shows up, the mission after the Norse gate is destroyed is to hold off the bad guy's horde until Odysseus comes and rescues you, in one mission of the Titans campaign you have to hold off the giant troll until the good frost giant can summon the dragon to kill it, etc. etc.
 * World in Conflict does this many, many times. About just as often as assaulting enemy positions, in fact. In some cases, it's not on a timer per se, but a secondary objective that remains active until the next primary objective is completed.
 * Multiplayer also has several maps with that type of gameplay.
 * Sacrifice does this in Pyro's seventh and ninth missions. In his seventh, you're being attacked by two wizards who both have way bigger armies than you; after five minutes, one of them disappears, and after a further ten (or if you manage to get near her altar) the other one snuffs it in mysterious circumstances. In the ninth, you have to fight off three wizards, one of whom was supposed to be on your side; after ten or so minutes, Acheron explodes because his God dies, making it (at least technically) possible to deal with the other two.
 * Oh, and Charnel's fifth mission has you desperately trying to defend a scythe that's having a demon summoned into it from a pair of righteous wizards. When the ritual is done, you get to use it against your tormentors.
 * Command and Conquer Red Alert featured a mission to protect the Chronosphere for what seemed an ungodly length of time given the siege you were under. The grim spectre of two dozen Mammoth Tanks descending on the base would have been devastating... were it not for the fact that they are so [dang] slow that the timer ran out before they could get there.
 * In Generals the Chinese had to defend a nuclear plant from the GLA until reinforcements, in the form of one bulldozer, can arrive.
 * And in Command and Conquer 3, a GDI campaign mission had you holding off Nod forces until reinforcements (in the form of an MCV) arrived. The catch was that thanks to low power, only a few of your defense buildings could be working at one time.
 * Sadly, or not, seems to be common theme in CNC games. A mission from C&C Covert Ops has you holding a small GDI outpost and scattered forces as they await salvation in the form of an MCV. If you didn't clear the Nod infested pathway at least somewhat (it comes in from the top of the map, your outpost is at the bottom), then you are done for - barring of course, luck.
 * A mission of Dune 2000 for House Ordos has you protecting a starport for 30 minutes. It doesn't matter if your base is destroyed in the process (and it will be unless you save scum enough to build appropriate defenses), because
 * Myth has defense maps. In one, the player has to protect a MacGuffin from Brainwashed former allies. In the second, they simply have to hold a hill to keep the enemy from crossing the river and disrupting the hero's plans.
 * Men of War loves this trope. Most of its missions have at least one objective that involves holding the line.
 * The The Lord of the Rings: Battle for Middle Earth series is filled with missions of this type. Two classic examples are Helm's Deep and the Battle of Pelennor Fields.
 * Total Annihilation loved these missions. Including two naval missions that were litteral hold the line missions. As well as the ever popular 'Surrounded and Pounded', near the end of the CORE missions and both final missions.

Role Playing Game

 * A battle late in Jade Empire has you defending inventor Kang the Mad from enemies while he rigs a bridge with explosives.
 * Neverwinter Nights: Hordes of the Underdark features two hold the line scenes played back to back as the invading army attacks on multiple fronts (though not at the same time), requiring you to move about the battlefield.
 * Kingdom Hearts II was especially fond of this, and in cases got pretty ridiculous. Especially when you first take control of Sora and have to fight a group of Nobodies, Sure, there are a lot of them and you're back to level 1, but you could so take them.
 * Final Fantasy VII had a minigame where you were supposed to send soldiers out to protect the phoenix egg... But it's much easier to just let them invade and fight them yourself.
 * Fable: The Lost Chapters has a side-quest wherein the player must protect an NPC while she recites a complicated spell.
 * Fable 2 has you defending Hannah aka Hammer from zombies as she fills a jug.
 * There's a variation of Hold the Line missions in which you have an ally preparing some strong attack, and you have to fend off the boss until it's fully charged. You usually have to do this several times. There are some examples in the Boktai series (Queen Hel, Vampire Ringo); another example is Ganondorf in The Legend of Zelda the Wind Waker.
 * One of the final missions in Vampire: The Masquerade Bloodlines pits you against a Werewolf. Since a Werewolf is effectively invulnerable and kills you with two or three blows, your only hope is to evade it for full four minutes until the tram that brought you there returns. Unless, of course, you looked up in a walkthrough, you cheater.
 * An earlier sidequest pitted you against a whole cemetery of zombies, whom you had to keep away from the gates for five minutes, until the real caretaker returned. The problem was that there are two gates on the opposite sides of the graveyard, an you have to defend them both against exponentially growing hordes of zombies...
 * Which is much more difficult and frustrating than it sounds.
 * Or, you could just play a female non-Nosferatu character and bone the caretaker, for the exact same rewards, or, for characters of either sex, you can bring him a prostitute.
 * The final chapter of Gustave's storyline in Saga Frontier 2 is a hold-the-line tactical battle, in contrast to the previous tactical battles. It could be won outright (in fact, the game has defeating the enemies as one victory condition), but this required a great deal of luck and would make holding the line impossible if unsuccessful.
 * Mass Effect: Despite being the current page quote for the trope, the mission that speech occurs during is a quasi-aversion; it's an ordinary mission for you, though it's implied that the NPCs offscreen are going through one on your behalf. However, there is a DLC mission, where you take on a simulation, of a mission by one of your commanders, which involves you waiting for 4 minutes fighting off wave after wave of enemies.
 * The page quote refers to a group of aliens preparing to Hold the Line off screen as a diversion for your attack..
 * Human mooks scream this endlessly while attacking.
 * The sequel has multiple missions of this type. The most memorable is probably the defense of Archangel, where you fend off an entire army of mercenaries trying to kill the local Vigilante Man.
 * The Mass Effect 2 Downloadable Content Arrival has this as a sort of Optional Boss: Holding the line against four large waves of exceptionally intelligent attackers and one Mini Boss in arguably the hardest fight of the entire game (for higher difficulty settings anyway). If you die, the mission continues to the next area. But if you succeed, you'll get an achievement, not to mention the attacker's fearful cries of how unstoppable you are, and another opportunity to flip off Cthulhu.
 * Mordin (who used to work with Kirrahe) uses this as an infrequent Catch Phrase. If you let him . Of course when you first mention Kirrahe to Mordin, the good doctor mentions how he did find the speeches somewhat stirring ... if excessive.
 * Parodied in the Lair of the Shadow Broker DLC, which includes dossiers on all the crew. Mordin's has a mission summary where he works with Kirrahe. Kirrahe repeatedly "reiterates the importance of holding the line," despite the fact that there is no line, and if there was it wouldn't need to be held.
 * In the demo and full game of Mass Effect 3 the first time is on Earth. Which pits you against a mob of mutated husks while you wait for the Normandy to pick you up.
 * The second time occurs during the salarian homeworld; Sur'Kesh
 * All multiplayer missions end with one of these as you wait for extraction from the area.
 * And in a somewhat meta example, Captain Kirrahe's signature quote was one of the primary slogans used by the game's fans to express their displeasure with the game's controversial ending.
 * Several times in Star Ocean 2 you will come across bosses that are immune to everything you throw at them, have defense so high that your attacks do almost no damage, and said bosses' attacks are nearly One Hit Kill . You may think of it as a Hopeless Boss Fight, but then you're staring at the Game Over screen. Turns out, you have to last X amount of time (usually 60 seconds) and the battle ends, and the story progresses.
 * This is done 4 times consecutively in the third Mega Man Star Force game, in which you have to defend valuable equipment from several waves of Omega-Xis clones. A slight Unexpected Gameplay Change ensues, since you fight them off on the field (read: in real-time) as opposed to the traditional Starforce method of turn-based battling things to death. You can fight each one individually using the traditional method if you have far too much time on your hands, since killing each one individually takes much longer than wiping them out on the field, and eventually becomes both overwhelming and generally a waste of time.
 * The final battles of every Paper Mario game start the boss off as being nigh invulnerable, and you simply have to hit it enough times and/or survive for enough turns before the game tosses you your Eleventh Hour Superpower.

Shoot Em Up

 * Missile Command could be considered an early example (1980), since you can never actually destroy any of the unseen enemies launching the enemy missiles at you.
 * Many classic, endless arcade games were like this; whatever enemy force you're up against never ends, so all you can do is hold it off as long as possible and aim for a high score.
 * The Ur Example is probably Space Invaders where the game is instantly over if the aliens reach the bottom of the screen.
 * In the final stage of the Touhou game Perfect Cherry Blossom, you have to survive the true spirit of Yuyuko, who is indestructible. This is repeated when you fight Kaguya and Eirin, or just Kaguya, in Imperishable Night. If you faced Kaguya, then once you reach this stage, you've already won.
 * Many extra stage bosses have similar attacks as either their penultimate or finishing spell cards.
 * There are a lot of these; the fandom likes to call them Survival Cards. EX-bosses and final bosses tend to have them the most often, although Stage 4 bosses Aya (Mountain of Faith) and Murasa (Undefined Fantastic Object) have one each to compensate for the fact that they have a fixed spell lineup rather than a variable one, which was customary until then.
 * What tops the cake, however, is that the whole game can be played like this. Each and every spellcard, and every nonspell pattern has a timer. Once the timer runs out, that portion of the boss's lifebar is defeated, regardless of how much damage they've taken. You can very well defeat a boss without firing a single shot. (however, some bosses intentionally ratchet up the difficulty of the pattern an insane amount on the final few seconds, mostly on patterns that is supposed to gradually get harder as the boss's HP is depleted, to prevent a cheesy win)
 * The final bosses of Radiant Silvergun and its spiritual sequel Ikaruga disable your weapons and force you to survive their attacks for 60 seconds.
 * Similarly, the final boss of R-Type Delta is immune to your weapons; the only way to beat it is survive until your Dose (effectively a Smart Bomb) meter slowly fills to max. The resulting blast is the only way to kill the boss.
 * R-Type FINAL has a tangentially-related gimmick for one of the final bosses; the only thing that can kill it is a fully-charged Wave Motion Gun shot, but it's broken and requires about 45 seconds of dodging the boss' Desperation Attack to sufficiently charge.
 * Many Gradius games have penultimate bosses that are huge, walk around slowly, and in most cases fall under this; they cannot be harmed by your weapons, only waited out until they self-destruct.
 * And the infamous Cube Rush in Gradius III Arcade's Crystal stage. The first game also did this with waves of a certain type of Mook before each fight with the Big Core.
 * Guns of Icarus: Each mission has a distance countdown marking how much farther you have to travel to reach your destination; you have to survive and protect your cargo until the Icarus makes it to the finish line. There is a twist--enemies will attack your engines, which makes the counter slow down and, if they reach critical condition, stop completely, so you've got to keep them repaired. The final stage, "Into the Breach", averts it by counting up instead of down for a survival mode.

Simulation Game
"Mission Control: Hold the line at Nav Alpha.
 * Several missions throughout the Wing Commander series are escort missions of your home carrier, buying time for it to make it to the next jump point.
 * Many space sims have this; Free Space had a few notorious missions where you were defending a ship or convoy, while wave after wave of Shivan fighters slammed into them, sometimes literally. You often wondered just just how vast some of those fighters' missile bays are, and how many of the "rare and elite" forces are actually in reserve...
 * The Rogue Squadron series also has many, such as defending a crashed Rebel ship from TIE bombers and ground forces.
 * One of the few mission types in Tom Clancy's H.A.W.X, so expect to see it several times. Can either take the form of keeping waves of enemy air, ground or naval forces away from an important stationary object, or an Escort Mission where you babysit a big plane (a bomber, an AWACS, or ).
 * Used several times during the course of the Mechwarrior series of games. One Mechwarrior 2 Mercenaries mission had an incredibly short briefing that invoked this trope by name.


 * Nav Alpha lights up on the map. It is surrounded by a dozen enemy contact signatures.*"

Stealth Based Game

 * Metal Gear Solid 4 has a few of these. One of them involved distracting a Gekko (a small mecha) until the MkII opens a door. The second one involves
 * One boss in Metal Gear Solid 2 cannot be hit at all; all you can do is dodge attacks until you get an important codec call.

Survival Horror

 * During the fight against Verdugo in Resident Evil 4, the player can either fight and kill Verdugo or survive for four minutes until the elevator arrives.
 * In addition, two sequences earlier in the game (the village and the cabin by the bridge) involved holding a house against zombie-like Ganados coming in every entrance. The former also includes Dr. Salvador in the mix.
 * As well as Resident Evil 5. The penultimate chapter's boss is against . The only way to get through is to survive for 7 minutes, or shoot enough that he decides to leave. On the other hand, shooting  too much results in a Nonstandard Game Over.
 * Both Pyramid Head battles in Silent Hill 2. Either shoot him/them until he leaves/commits suicide, or dodge him and wait it out.

Tabletop Games

 * This is essentially the mission of the French and the British in Avalon Hill's Third Reich for the first few years: hold out until the Soviet Union and the United States enter the war. In most cases, of course, France will fall; the question is when. The longer the French hold out, the better shape the Allies will be in later on.

Tower Defense

 * This is the point of the entire genre of "tower defense" games: a series of enemies are attempting to get from point A to point B along a ridiculously torturous path, and it's your job to kill them all before they get to point B.

Turn Based Strategy

 * There are several of these in Fire Emblem. The fourth mission of Blazing Sword, for example, has you protecting an injured woman from bandits in a crumbling building.
 * Radiant Dawn had a literal hold the line chapter, in which there was a thin blue line that that your Lord could not cross (your Lord receives a long-range magic spell to make up for this) and no enemies could be allowed to cross - this became rather annoying when enemies that could fly appeared - since you would never have enough people to cover every block of the line, you would often fail the chapter when one of the hawks decided to attack one of the people holding the line, causing a Game Over instantly, when the hawk in question had 1HP left.
 * Final Fantasy Tactics a 2 has a few missions where the enemy needs to be kept away from a certain area. Which is easier than it sounds because the AI doesn't seem to know that and will simply fight as usual. Just make sure the AI doesn't walk in there because of facing advantages... Not all of them are timed, mind you. Some of them require you to both defend a specific area AND defeat all the enemies.
 * Jeanne D Arc has several of these missions, such as defending the gates of orleans or keeping alive with no room for error.
 * A popular online maptype in Battle for Wesnoth is the "Survival" game, in which players cooperate against waves of themed enemies.
 * In Scenario 4 of Langrisser, the hero and his guardians are ambushed in the night by a pack of slimes, who are extremely strong against conventional attacks from your soldiers. His goal is to survive long enough for the slimes to get bored and retreat. On the fifth turn, reinforcements arrive bearing weapons that can kill most of the slimes easily.

Turn Based Tactics

 * The entirety of X-COM: UFO Defense is a Hold the Line mission. Every alien ship and base the player destroys only serves to hinder the aliens' progress until the player has the knowledge and technology to attack the alien home base. No matter how many weapons the player builds and no matter how many aliens he successfully destroys, the Earth will slowly but surely fall into alien hands unless the final mission is carried out.
 * This is mostly true for most of the games in the X-COM series and even lots of those inspired by it. In X-COM: Terror from the Deep this unsurprisingly is pretty much the same as in the original. In Apocalypse, you actually take the fight to the enemy after a while (however, mostly you'll be holding the line at home while you carry out covops-style missions in the alien dimension. And the only way to actually win is to destroy the one last buildings the aliens have - and you can't skip buildings). In X-COM: Interceptor you are delaying the . In UFO: Extraterrestrials, you are holding the line to prevent the alien mothership . Again, in the end you go and kick their ass. Most of the time though, you are fighting against better equipped and numerous aliens which are out of your reach.

Visual Novel

 * In case 4 of Phoenix Wright: Justice for All . In an odd turn of events, you can defend the line too well by.

Wide Open Sandbox

 * This shows up in Prototype via a mission where you have to protect a doctor locked in a reinforced room from mindless hunter drones for four minutes. This mission is particularly annoying because you are stripped of roughly 75% of your combat options and are forced to use guns to fight effectively, some of which damage the structure the doctor is holed up in due to splash damage.
 * And in another mission where you have to defend a stationary vehicle while it pumps anti-virus gas underground to flush out the Big Bad.
 * Black Watch's whole "We are Black Watch, we are the last line of defense. We will burn our own to hold the Red Line, it is the last line to ever hold" deal.

Anime And Manga

 * The Crown Game in Tower of God consists of getting on the throne and wearing the crown and then defending it from all the other trios. It is set in five rounds a ten minutes with new contestants being able to enter each new round and the crown holder being the only ones who entered who are allowed to proceed to the next round, where they had to defend the crown. This lead to such moments as Koon's glorious trolling, Hwa Ryun's Curb Stomp Battle against everyone, the (re)introduction of several characters and a glimpse of the main characters potential.

Collectible Card Game

 * A Magic the Gathering card goes by this very name. It gives blocking creatures +7/+7 (to their ATK/DEF) until end of turn. To put it in perspective, a similar card called "Righteousness" is the same rarity but only works on one creature. Hold the Line works for two or two dozen creatures.
 * Yu-Gi-Oh players who use cards such as Exodia and Final Countdown need to stay alive long enough complete its requirements. Exodia requires the player to collect all 5 Exodia cards, and Final Countdown requires the player to last at least 20 turns to win the duel. Players who use them would usually wall themselves with monsters with high ATK or DEF till they can complete all the requirements.

Tabletop Games

 * In Warhammer 40000, The Crimson Fists Chapter Master Pedro Kantor has the "Chapter Tactics" special rule. This means that, in addition to his forces exchanging the "And They Shall Know No Fear" special rule for the "Stubborn" special rule, all Sternguard Veterans (Elites) gain the "Hold The Line" special rule, allowing them to hold objectives like other Troops.
 * The victory condition in Infernal Contraption is to be the last one with cards remaining in your Parts Pile.

Live Action TV

 * In Babylon 5, the final battle of the Earth-Minbari war is The Battle of the Line, a massing of Humanity's remaining ships in an attempt to hold off the Minbari for as long as possible to evacuate as much of Earth's population as can be. At the end of the battle the Minbari surrendered to the badly beaten Earth forces.
 * Several of the games on Minute to Win It require the player to keep up an activity for the full 60 seconds, rather than finishing the stunt within the time.
 * The primary objective in the original Japanese version of Run for Money Tousouchuu is to simply avoid getting tagged by a Hunter until time runs out. The second the clock hits 00:00, everybody left standing wins the jackpot.
 * There's a new show in the UK called Cleverdicks (yes, that's really the name of the show). The final money round requires the contestant to answer questions quickly enough to prevent the stack of questions from reaching the top of the game board (you can have 8 questions queued up and stay in the game) for two full minutes.
 * The battles at the end of seasons 5 and 7 of Buffy the Vampire Slayer have elements of this, as they have to hold back forces that only have a certain time window to achieve their tasks. Buffy even says the trope name to Faith as she hands over the leadership after being  mortally wounded.

Music

 * Love isn't always on time. Woah, woah, woah.

Real Life

 * The Greeks at Thermopylae and Artemesium attempted this tactic during the Second Greco-Persian War. The fleet at Artemeisum managed to hold their line. The Spartans at Thermopylae... not so much.
 * The "Thin Red Line" at the Battle of Balaclava, 1854. The 93rd Highlander Regiment in a two-man deep firing line successfully routed a Russian cavalry charge, saving the vulnerable British camp in the process.
 * Second Battle of Ypres. After the Germans used gas for the first time the French colonial units in position broke and ran leaving a 7 kilometer wide hole in the line. Before the Germans could take advantage, the Canadian First Division (responsible for defending a front a few hundred meters wide) along with some scattered French troops spread out to plug the breach, holding the line for a critical 48 hours in hastily thrown up defenses until reinforcements could be brought up. One in three of the Canadians were wounded or killed.