History Main / GameplayAllyImmortality

** On your first playthrough of the game you will spend much time and effort [[EscortMission babysitting]] Ashley to prevent her from being hacked to death by mutants or being grabbed and carted off by mad cultists. However, an unlockable costume dresses her in a full suit of plate mail. This makes her completely immune to damage and also makes her so heavy that enemies cannot pick her up to abduct her.

** [[DownplayedTrope Downplayed]] in ''VideoGame/ResidentEvilRevelations2'' in that the partner characters (Moira Burton and Natalia Korda) are not completely invulnerable to damage. Instead, they have [[RegeneratingHealth Regenerating Health]] that slowly gains back by not taking any damage in a few seconds, unlike the main characters Claire Redfield and Barry Burton who take damage as usual. Very useful in Moira's case since she has a very powerful ground finishing move with her [[CrowbarCombatant crowbar]].

* Several ''VideoGame/SonicTheHedgehog'' games feature AI partner characters who can do most of the same things the player can, and can get killed numerous times (often due to [[ArtificialStupidity wandering into hazards]]) only to [[StayingAlive come back a short time later]]. The classic form of this, made famous by ''VideoGame/SonicTheHedgehog2'' and ''VideoGame/Sonic3AndKnuckles'', is an option where you can play as Sonic and have Tails following you invulnerably and with the capacity to be controlled by another player instead of the AI; this makes boss fights a lot easier if you have a friend playing with you, or can position Sonic somewhere safe and pick up the second controller yourself, as you can have Tails attack the boss without worrying about taking damage.
** This has been abused in the "[[https://www.youtube.com/watch?v=7Y5syE67H68 Tails Abuse]]" series of videos, where Tails is shown [[VideogameCrueltyPotential getting hurt/killed multiple times only to come back for more pain]].

* ''VideoGame/SuperSmashBros Brawl'' subverts this trope during the Subspace Emissary in co-op. Player 2 can fall off the stage and be put back on it, but if an enemy attacks the player and they get pushed too far off screen, it counts as a KO. And when you get caught in a non-escapable battle, falling off the stage still counts as a KO for player 2.

* In the ''[[Videogame/{{X}} X-Universe]]'', plot important ships cannot be killed or [[BoardingParty boarded]]. The [[MileLongShip Argon One]] in ''X3: Reunion'', for example, cannot be brought lower than 93% health with friendly fire. A GoodBadBug in early versions of ''X3: Terran Conflict'' allowed the player to acquire a [[SpaceTrucker freighter]] that never had its invulnerability flag removed after the pilot ejects, giving them a completely indestructible and [[ActualPacifist completely unarmed ship]]; better practice your [[RammingAlwaysWorks ramming skills]].

->'''Jedi Exile''': But to get back up after being that wounded?\\
'''HK-47''': Observation: It does seem unlikely, master, but I have observed that you -- allies included -- seem to be able to recover from the most grievous of injuries, and quickly as well.

** In the final battle of ''VideoGame/TheLegendOfZeldaTheWindWaker'', other than a scripted moment where she is KO'ed, Zelda cannot be harmed during the battle (though she does wince in pain); you can't kill her, even if you repeatedly slash her with the Master Sword.

** In ''VideoGame/TheLegendOfZeldaSpiritTracks'', Zelda gains the ability to control phantoms, which are giant armored knights. She can't be killed, but some attacks will stun her, she'll panic from the sight of rats, and [[spoiler: the final boss can take control of her and make her attack you.]]
** In ''VideoGame/TheLegendOfZeldaBreathOfTheWild'', the four allies who help you board the Divine Beasts cannot be harmed by either you or the Divine Beasts.

* A few missions in ''VideoGame/JediAcademy'' have the player fight alongside legendary badass Kyle Katarn. As you might imagine, he's insanely difficult to kill, as the game gave him superhuman reflexes, near full Force power, and more than double the HP of the Final Boss. Mooks can't kill him; the only way he can ever die is if you're unfortunate enough to encounter a [[GameBreakingBug Game-Breaker Glitch]] which causes Kyle to accidentally treat you as an enemy. (This has one of two outcomes: You die, or you manage to kill him after an insane amount of effort, in which you [[EscortMission are rewarded for your effort by failing the mission for letting your ally die.]])
** He can also get stuck in a giant trash compactor at one point. You are killed within a few seconds in such cases; the Badass survives considerably longer, but ultimately his HP run out.

* In ''VideoGame/KingdomHeartsI'' and ''VideoGame/KingdomHeartsII'', you allies will get up a few minutes after losing all their health. If you lose all your health, however, it's an instant game over. The in-game justification for this is glossed over ''very'' quickly, but basically boils down to your partners simply being knocked out, and Sora ''losing his heart'' any time he dies. Because the Heartless/Nobodies are very vulnerable to the Keyblade, they don't take any chances.

* Late in ''VideoGame/ShinMegamiTenseiIIINocturne'', [[spoiler:all of the Manikins]] are killed except for the shopkeepers. [[https://archiveofourown.org/works/39865635 all out of vacation days]] pokes fun at this and offers an explanation: all shops are invincible. The shopkeeper, the shop itself, and the merchandise cannot be attacked or damaged. The shopkeepers take advantage of this to [[spoiler:rescue the surviving Manikins. Anyone hiding behind the counter is classified as merchandise, but the shopkeeper can refuse to sell them]].

* In ''VideoGame/HalfLife2: Episode 1 & 2'' Alyx isn't exactly invincible, but (unlike you) her health regenerates extremely rapidly, making it unlikely for her to die unless you deliberately sit back and let her get mobbed by multiple enemies. Most named allies in the game are the same way, and the game designers try to engineer situations where this isn't actually shown and pull it off for the most part.
** The [[BokeAndTsukkomiRoutine Abbot and Costello pair]] in ''Episode 2'' can, according to commentary, hold their own against the Antlion horde. You, however, will get your face chewed off.

* ''VideoGame/ResidentEvilRevelations'' and ''VideoGame/ResidentEvil6'' both play this trope straight (provided you're on single player), seemingly in response to complaints about Sheva Alomar being responsible for [[ArtificialStupidity 95% of the deaths and losses, and 100% of the frustration]] in [[VideoGame/ResidentEvil5 her game]]. The trade-off, of course, is your partner either cannot use guns or cannot use them with much effectiveness.