Purpose-Driven Immortality

Agatha: How old are you?
Embi: Mmmmm—I am not sure, but 130 in the least [...] When I was young and rash, I made a sacred vow to see the world before I died. Frankly, I didn't know how big it was at the time.
Agatha: ...But what has that got to do with your long life?
Embi: One of the problems with people here is that they do not take sacred vows at all seriously!

— Girl Genius

You are a Determinator. You have a mission in life, and you are going to accomplish it. You don't care how hard it is or who is standing in your way. You're going to do this, even if it takes a thousand ye...

What's that? It is going to take over a thousand years? Phooey.

Fortunately, thanks to a bit of Applied Phlebotinum, even this won't stop you from reaching your goal. If you need a thousand years, you'll find a way to live a thousand years, or ten thousand, or a million. However long it takes.

This trope is when someone is given an extended lifespan in order to accomplish a particular task. Until the task is accomplished, the character is immortal, but once it is, the character either dies or goes back to an ordinary lifespan. Sometimes this is a source of relief for the character because Who Wants to Live Forever? In other cases, Living Forever Is Awesome but accomplishing this goal is more important.

Ghosts and Revenant Zombies with Unfinished Business usually have Purpose-Driven Immortality, with their spirits moving on as soon as the business is finished.

A subtrope of Immortality. Compare Flying Dutchman, where characters are given immortality but no purpose to fulfill.

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Examples

Anime and Manga

• Ayakashi in Ayakashi Triangle do not age, but generally have some sort of action that's fundamental to their existence. Sometimes these are Ghostly Goals they fulfill to cease existing, but more commonly they're repeatable activities done to continue existing, that vary from the mundane (painting, counting beans) to the extremely harmful (eating humans or other ayakashi, forcing people to kill themselves). It also seems possible, if difficult, for an ayakashi to change what their purpose is, as Sosuke goes from eating ayakashi to trying to redeem himself for those he's killed.
• Downplayed with Baki the Grappler's Speck. This muscular, invincible fighter who appears to be in his forties lives hoping to find such a formidable opponent that would show him an undeniable defeat. When this finally happens, his body undergoes a physical change as he loses his muscle mass, now resembling his actual age, as he is over eighty years old.
• Takashiro of Betrayal Knows My Name takes a duras into his body in order to extend his life throughout multiple reincarnations of the villain. He tells the protagonist (also re-incarnated) that he intends for this fight to be his last, however.
• In Blade of the Immortal, an old woman specialized in giving kessen-chu, sacred worms who make anyone infested with them very hard to kill, and keep them as they were when they received this "gift". One way to remove these worms is to finish one important task.
• Sai from Hikaru no Go. He was a Heian Go player that after committing suicide haunted a Go board, possessing first the kid who will become Honinbou Shuusaku and then Hikaru, of the Protagonist Title. At first, the characters and the audience believe that this was due to him wanting to play Go even after his death and due to him wanting to achieve the Divine Move (a.k.a The Hand of God). Later we find that indeed there was a purpose for him returning as a ghost, but it wasn't his purpose; he was allowed to remain in the land of the living for him to be Hikaru's Mentor.
• In arc 5 of Jojos Bizarre Adventure we have Bruno Buccellati who is killed early by the Big Bad, but due to his strong will it doesn't stick, though from that point forward he never bleeds or feels pain, and although characters notice this occasionally they rarely make comments aloud. However, at the end of the series, he immediately passes away for good, having accomplished his goal.
• Odago Koinosuke in Jubei-chan was given a command to find a successor to Yagyu Jubei, an oath he took with Undying Loyalty, literally. If in danger of failing his oath, he desiccates on the spot and just as quickly revives.
  • His daughter in the sequel has a similar impetus, except she turns into a tree should failure be imminent, and this is not done with as much aplomb.
• In Naruto, Orochimaru strives for immortality so he can learn all jutsu. According to his former friends, his goal was originally to live long enough to meet his dead parents' reincarnations. He became so obsessed with achieving this that he was willing to start crossing moral lines to become powerful enough to accomplish it, eventually becoming consumed by the pursuit of immortality and power as ends unto themselves.
• Panty & Stocking with Garterbelt: Garterbelt literally cannot die (he's surprised to learn this when he's brought back in reverse from an explosion) until he's fulfilled whatever mission God has given him.
• In RG Veda this trope is played with Kaara. She was a human who was given the lifespan of a god by joining a god's Clan as a priestess, but she commits suicide out of guilt for not stopping her sister's betrayal. She's given a new purpose by Ashura-Ou, to protect the sword Shura-to until the new successor comes to reclaim it, and she waits 300 years for Ashura. Once Ashura takes the sword plus one of the sword's seals, she dies as the borrowed life she had was no longer needed.

Comic Books

• Implied in Baltimore with Baltimore himself. Right after the Red King is killed, Baltimore himself dies, having previously removed his own heart. It was implied God had kept him alive for this single goal.
• In The Crow, the revenants resurrected by the title bird are resurrected and given invulnerability until they've avenged their own or their loved ones' deaths. The movies gave them an Achilles' Heel in the form of killing the bird in order to make them mortal again, which villains often try to exploit in order to give the climax dramatic tension.
• The Sorcerer Supreme is The Ageless — partly to give him a decent term of office, partly so that he can study and improve his mastery of the mystic arts without having to worry about getting sick, getting old, or dying. (Of course, he can still be killed...)
• Marvel Comics has the Elders of the Universe, who are generally immortal because they have an overwhelming goal: collecting, game playing, combat, and so on.
  • They are each the Last of Their Kind during the early days of the universe so they were granted this immortality. However, the most famous one, the Collector, lost his wife to Death when she found no more reason to live and her immortality failed her. As such, each of them pursued a never-ending hobby to give them purpose and not succumb to the same state of apathy.

Fan Works

• Child of the Storm eventually reveals that Doctor Strange's immortality is based entirely around the purpose given to him by the Time Stone — to carry out a Long Game designed to fill the world with heroes and unite them in the common cause of facing down Thanos when the time comes.
• In Pages Of Harmony, Twilight intends to become immortal so that she can help harmony reign over chaos forever... after killing all the disharmonious through analyzing the Elements from her friends she killed.
• The Petriculture Cycle: In π, it's established that Alicorns cannot die unless they actually want to - they are immortal and invulnerable until they are good and ready to give up their lives. Twilight Sparkle and Pinkie Pie vow not to pass on before Penumbra, because they don't want her to be lonely again.
• The Return of the Guardians trilogy spins guardianship this way. While a Guardian's strength comes from children's belief, true to the source material, immortality comes from performing their duties. Passing the job along to someone else gives them the opportunity to lead a mortal life. The Keeper is the second Father Time, and Angel is the fourth Cupid. Mother Goose declined immortality, and grew old and died without choosing a successor. By the end of the series, the Man in the Moon/Prince Ioniel names Jamie a candidate for her title once he grows up.

Film

• In The Crow (1994) it seems that the same rules apply as in the comics. As long as the titular Crow is alive, the person they brought back is immortal and has a Healing Factor. This becomes a problem when Eric loses his immortality because he's already finished off every member of the gang who previously killed him and his girlfriend, but the crime lord who ordered the murder (and was thus indirectly responsible even if he might be the most culpable) is still breathing, so Eric's soul still can't rest in peace.
• In Hocus Pocus, Thackery is transformed into a cat and given Resurrective Immortality until the Sanderson sisters are defeated. And since they're Sealed Evil in a Can, he first has to wait for them to be unsealed. At the end of the movie, he finally joins his dead sister in the afterlife, regaining his human form.
• In Indiana Jones and the Last Crusade, the Grail Knight is given immortality in order to complete his mission in regard to the grail.
• It's implied (at least in The Film of the Book) that the reason Orlando never ages is because he promised Queen Elizabeth he wouldn't.
• A Downplayed Trope in Mr. Magorium's Wonder Emporium. The titular Mr. Magorium found a great cobbler a long time ago and bought enough pairs of shoes to last him for the rest of his life. Over 200 years later, he's finally on his last pair and is ready to die.
• In Santa Claus: The Movie, Claus and Anya (the future Santa and Mrs Claus) are given immortality along with their elves, so that they can make and deliver toys to the good children of the world in perpetuity.
• In Thor: Ragnarok, Surtur explains that he cannot truly die until he achieves his purpose of destroying Asgard during Ragnarok. Even if he is killed, he'll eventually come back. He eventually succeeds in his purpose, and he's apparently killed in the explosion that destroys Asgard.

Literature

• Glaeken from The Adversary Cycle and Repairman Jack novels lived for thousands of years without aging, so long as he was the Ally's champion. When he thought that he'd destroyed his foe Rasalom in The Tomb, his immortality left him and he began to age normally. Genre Savvy Rasalom had taunted him with the prospect that he might instantly age to dust if this happened, but the Ally wasn't quite so callous as to permit that.
• In the Animorphs Megamorphs book Elfangor's Secret, the team learns that in return to being sent to the past to complete a mission, one of their members will have to die. Later, after the death of one of them, the rest of the team discovers that they can't be killed, because only one of them was meant to die on the mission, making them effectively immortal until the mission is completed.
• In the Belgariad and related books, it's stated that wolves live "as long as they need to" and is implied that the same is true of sorcerers, given that they all have a mission from the gods to fulfill. But in the epilogue, none of them show any sign of getting ready to die off.
• John son of Zebedee, who in the Christ Clone Trilogy becomes one of the Two Witnesses, who then dies and is resurrected by God to enter into heaven.
• In The Dark is Rising, as a punishment for betraying the Light, Hawkin is forced to become the Walker and carry the Sign of Bronze for seven hundred years. He's hounded by the Dark all the while until the time comes for him to give it to Will Stanton, the last Old One.
• In one of the flashbacks chapters of the first Deverry novel, a young Prince Galrion, who had recently been renamed Nevyn, knelt before the grave of his ex-fiancee and swore that he would not rest until he had set right the mistakes that had led to her death, the death of her brother, and the death of another of her suitors. The gods made him keep that oath - he was around 450 when he finally died. In addition, an entire Civil War happens that could have been averted if he and Brangwen had married - requiring him to fix that, too.
• Pete Hamill's Forever had a protagonist given immortality until he found his true love (as long as he didn't leave Manhattan).
• This is the basic plot of the Indigo books. Princess Anghara releases seven demons from the Tower of Regrets, and is made immortal so she can re-capture them all.
• Schmendrick from The Last Unicorn had a powerful magical gift, but none of his tutors were able to help him access it. Finally, out of frustration, one of the tutors cast a spell on him to make him immortal until he learned how to use his magic.
• In the Morgaine Cycle, Morgaine set up the gates to reset the physical ages of herself and her companion Vayne as they pass through them, so as to complete their mission of closing all gates in the network in question.
• The Raven Tower: The god called the Raven appoints a human "Raven's Lease" to rule on his behalf, who cannot die during their tenure — anyone who tries to kill them drops dead on the spot. The only way the Lease is allowed to die is through voluntary Human Sacrifice to the Raven at the end of their term.
• In Skate the Thief, Belamy turned himself into a lich because he feared he would die before tracking down the man he believed killed his beloved daughter. After catching up to the man (his former apprentice), he seems to have resigned himself to spending the rest of eternity reading as many books as he can.
• This is the reason for the anti-aging spell on the Palace of Prophets in The Sword of Truth series: The sorceress at the Palace can train a wizard, but not very efficiently. The spell is necessary to ensure that the wizards and sorceresses live long enough to finish the training.
• "Three Days In Undead Shoes" features a former special forces zombie who is driven to protect the main character, considering her to be his mission.

Live-Action TV

• The Inquisitor from the Babylon 5 episode of the same name reveals he was originally kidnapped from late 19th century Earth, where he was better known as Jack the Ripper. The Vorlons kept him alive for the purpose of interrogating would-be messiah figures. When he actually finds two who are worthy of being the Messianic Archetype in Sheridan and Delenn, he says that he hopes he is finally done and that the Vorlons will let him die.
• In Dead Like Me, Reapers exist in a state of functionally immortal undeath, until they eventually move onto the afterlife.
• In Forever Abigail believes this is true for Henry's immortality.
  Abigail: Henry, listen to me. Everything you are, everything you've learned is for something bigger. You were made like this for a reason, but it wasn't for me.
• Lost:
  • Richard Alpert is revealed to have been rendered immortal by Jacob, in order to serve as his Herald and carry his instructions to the Others. After Jacob's death, he remains immortal until a new protector of the Island is chosen, which coincides with his decision to finally leave the Island for good. As he does, he finds a grey hair, indicating he's begun aging once more.
  • After becoming the new protector of the Island, Hurley offers Ben the same role. It's later implied they spent several decades or even centuries doing good work together, before deciding to move on.
  • A darker version occurs with Michael. After leaving the Island, he discovers he is unable to die even after several suicide attempts because the Island isn't done with him yet. Upon his return, he's finally granted his wish.
• The TV series New Amsterdam (2008) had a similar premise to Forever (see Literature) with the main character John Amsterdam, a Dutchman from the 1600s who became immortal via a Native American woman's spell, which can only be undone once he finds his One True Love (though he didn't have the "don't leave Manhattan" part). It led to some plagiarism accusations.
• Jiminy Cricket from Once Upon a Time. The Blue Fairy promises Jiminy that he will live as long as he needs to in order to help Geppetto.
• Stargate Atlantis had an episode where an alternate version of Dr. Weir used suspended animation to extend her life long enough so that she could see to the maintenance of Atlantis from the time the Ancients abandoned it until the time the team arrived.
• The episode "The Vengeance Factor" of Star Trek: The Next Generation discusses a clan war in the history of the planet the Enterprise is visiting. A clan called the Lornak wiped out another clan, the Tralesta. To get their vengeance, the Tralesta survivors made their last member effectively immortal and made her the carrier of a virus to which only the Lornak were vulnerable.

Radio

• In The Hitchhiker's Guide to the Galaxy (1978), Wowbagger the Infinitely Prolonged at least thinks it's his purpose in life to insult everyone in the universe, and he does get his immortality revoked after insulting the last person on his list (the great prophet Zarquon). Does not apply in the novel (Life, the Universe and Everything), where he was made immortal in a random accident and gave himself the task of insulting everyone in the universe because he'd run out of things to do to pass the time.

Religion and Mythology

• Older Than Feudalism: The Gospel of Luke in The Bible has an example in Simeon.
  "Now there was a man in Jerusalem called Simeon, who was righteous and devout. He was waiting for the consolation of Israel, and the Holy Spirit was on him. It had been revealed to him by the Holy Spirit that he would not die before he had seen the Lord's Messiah."

  Luke 2: 25-26
  • He does end up meeting him when he's brought in for Jewish baby ceremonies.
• Part and parcel of the Revenant Zombie. Revenants were the original undead, humans who died with a purpose so strong it could even override death, such as love or revenge, and could only die when their reason for coming back had been resolved.
• In Ramayana, it is said that Hanuman is immortal to sing praises to Rama, and will continue to be so as long as Rama's name is praised by anyone. That means Hanuman is virtually immortal until there's no devout anymore, from which at that point he would die and the world would go into a judgment day.

Roleplay

• Destroy the Godmodder: The reason the players of the series are invincible and can't be killed by the Godmodder is that the literal force that dictates the plot of every story in reality is on their side, giving them the ability to both do whatever they want and to not be killed directly (or at least, to have their deaths not matter much) just so that they can accomplish the titular goal, in a very extreme case of Plot Armor.

Tabletop Games

• Changeling: The Lost: Downplayed with the Office of Vizieral Council, an Entitlement whose members remain The Ageless for as long as they keep their oath to serve as The Good Chancellor to their Monarchs.
• The Risen Martyr class from the Dungeons & Dragons splat Book of Exalted Deeds resurrects a killed character, then kills them again as soon as they accomplish the goal they were resurrected for (or they reach the final level in the class and they can't multiclass further, though they can exploit the rule that says you don't have to level up). Intended for games with no resurrection but infamously bad in mechanics.
• Jefferson DeGrey in the Fantasy Strike universe was given immortality that will last until a vaguely-defined "true purpose" of his is completed. Until then, he is accompanied by a ghost woman who keeps him focused on finding out what that purpose is.
• All ghosts in Pathfinder function like this. They have a specific goal or purpose, and fulfilling that objective is the only way to permanently get rid of them. Until that happens, reducing their HP to zero just causes them to rejuvenate a few days later. Unlike most examples of this trope, they are usually incapable of fulfilling their purpose on their own but require help from the living to do so. Naturally, discovering and taking the correct actions to aid their passing usually falls to the PCs.

Video Games

• Bloodborne: In the opening cutscene, the player signs a contract that binds them to hunt the beasts plaguing Yharnam, and in exchange allows them Justified Extra Lives by reviving in the Hunter's Dream upon death. So long as they haven't killed the final boss and returned Yharnam to some tattered semblance of normality, they'll come back again and again. Once you do, Gherman will offer to free you from your contract by killing you in the Dream. Accept, and he'll live up to his promise. Refuse, and he'll fight you as a boss to force you out.
• The protagonist of The Cat Lady is given the ability to revive upon death so she can confront and kill a series of serial killers known as "parasites".
  • Taken up to 11 if you refuse the Queen of Maggot’s help to resurrect one last time, in which case Susan comes back just by being too determined to die.
• In Dark Souls, this acts as Justified Extra Lives. Undead, like the player character, will inevitably return from death at the last Bonfire they rested at, but this comes at the cost of a little bit of their humanity- both figuratively and the in-game item known as Humanity (which is needed to return to human form after a death). As long as they can maintain a purpose (Solaire seeking a personal sun, Siegmeyer being an adventurer, Andre being a blacksmith, Laurentius looking for Quelana, the player trying to complete the game, et cetera), they can live forever. If not, they'll lose their sanity and turn into mindless Hollows who die permanently when killed- a fate that befalls multiple characters as their quests are progressed. Some of those who don't (such as Andre and Patches) are later seen in Dark Souls 3, untold ages later, looking just the same as they always have.
• In Dawn of the Dragons, this was forced upon the premium general Mathias the Masterer. The gods were disappointed in him wasting his vast potential, so they cursed him with an eternal life that would only end after he had mastered every skill in existence.
• In Dragon Age: Origins, the Guardian of the Urn of Sacred Ashes implies that his vigil over the final resting place of Andraste will last as long as the Urn exists, or when the last bastion of the Tevinter Imperium finally crumbles into the sea.
• Drakengard 3 reveals that the series' Dragons have the power to reincarnate upon death. They can also sacrifice this power to grant a Wish. In other words, Dragons can live as long as they desire until they find something or someone worth dying for.
• Elden Ring: It's somewhat vaguely-described, but it seems that the Guidance of Grace that revives your character only works so long as you continue to seek to fix the Elden Ring. Many Tarnished characters will mention that they can't see Grace any more, and the only ones it's confirmed still do are you, Sir Gideon Ofnir, Goldmask, and Hoarah Loux.
• Fate Series
  • In the Heaven's Feel Route of Fate/stay night it is revealed that Zouken Matou originally had this back when he was Zouken Makiri. After the first Heaven's Feel failed, he transferred his soul into his Crest Worms to extend his life, in hopes of eventually winning the Holy Grail and creating the Utopia he and Justeaze Eizbern wished for. Unfortunately, over time the constant moving of his soul had twisted him into the sadistic monster he was in the present day. He still wants the Grail, but can no longer remember why he wanted it in the first place.
  • In the Sixth Singularity of Fate/Grand Order, it turns out that Sir Bedivere was a long-live human rather than a Servant as initially thought, having lived from the fall of Camelot to the age of the crusades after failing to return Excalibur to the Lady of the Lake and preventing his king Altria from dying, leaving her to become a wandering spirit and eventually the Goddess Rhongomyniad. Bedivere had spent centuries wandering the world to find his king and give her back Excalibur, leading him to end up in Avalon. From there Merlin sent him to the Sixth Singularity to find Altria. Thanks to Chaldea, he is able to meet face to face with Goddess Rhongomyniad, giving her Excalibur to return her to Altria and finally letting him die in peace.
  • In the "Saber Wars II" event, the backstory reveals that when the Primordial Goddess was defeated in the Servant Universe, she "rewarded" Calamity Jane and Space Sigurd, the only survivors of the Servants that fought her, with immortality until the day she rises again. After her resurrection, Ashtart Origin almost casually dismisses it when she revives and remembers Jane, implying that the latter is no longer immortal.
  • Faeries function like this in the Sixth Lostbelt as they neither age nor require sustenance, simply born with a function to fulfill and as long as they stay true to this purpose, they can remain immortal. Faeries that forget their purpose eventually suffer thorough Loss of Identity since it's core to who they are and will decay into Mors. Faeries that remember their purpose but cannot actively fulfill it will drive themselves mad and mutate into a Nightcall. Unfortunately, a faerie's purpose can easily place them at odds with other fairies, and since fairies are willing to do anything to fulfil their purpose and aren't bright enough to take a long-term view, this causes constant conflict. For a perfect example, see Aurora, who ended up causing the end of the world because her purpose is to be the most brilliant and beautiful faerie, so she kills anyone who might surpass her... even if they were, like Lostbelt Morgan, extremely important to the lostbelt's survival.
• Final Fantasy XIII-2 has Caius, who is given immortality so that he can be the guardian of the seeress Yuel in all her incarnations. He implies that he can be killed only by someone else worthy to be a guardian, who will then take his place. In the end, Noel ends his life, but without becoming the new guardian. However, the death is revealed to only have been temporary in The Stinger that's only seen upon getting all of the fragments, for reasons later explained in Lightning Returns: Final Fantasy XIII.
• Rose in The Legend of Dragoon is given a charm to prevent aging in order to have enough time to atone for a mistake made during the original Dragoon War (namely, releasing the Virage Embryo, a creature designed to bring about the end of the world).
• The Magypsies of Mother 3 live as long as their needles aren't pulled, since it's their job to guard their needles. Once their needles are finally pulled, they disappear.
• The Other: Airi's Adventure: What appears to be a ghost with Unfinished Business, since she fades away after it's done. That business is done in the mountains, and it's getting out the cave she was apparently trapped in.
• Vhailor from Planescape: Torment is driven to enforce justice amongst the planes. The fact that he's long dead (his body has long since turned to dust) will not stop him from fulfilling his duty. If you point out to him that he's dead, Vhailor will point out that this doesn't matter: Evil exists, and evil must be punished. With very high Charisma and Intelligence you can point out to Vhailor that the number of already dead lawbreakers outnumber the currently living ones, causing him to pass on in hot pursuit of them.
  • This also applies to Deionarra, whose spirit still remains bound to the world in order to help the Nameless One's quest. Turns out that one of the Nameless One's past incarnations tricked her into falling in love with him so that, when she died, her spirit would've stayed to help all eventual future (and amnesiac) incarnations. And he deliberately set up her death. This is regarded as one of the most evil acts in the entire story.
• In Sly Cooper and the Thievius Raccoonus, the Big Bad Clockwerk tells that his hatred and desire for revenge on the Cooper family kept him alive for centuries. Gradually replacing all his body parts with mechanics helped, but it's revealed in the second game the only thing even keeping his mechanical parts going was his Hate Chip: a device that fueled him purely off The Power of Hate. With his Hate Chip destroyed, even his mechanics swiftly rust and decompose into nothing.
• In Solatorobo: Red the Hunter, Elh and Béluga were "blessed and cursed with" immortality so that they could fulfill the purpose of sealing away Lares and Lemures whenever either one was to reawaken, as the rest of the Paladin Clan were wiped out in the destruction of their homeland. By the time the game starts, the two haven't physically aged in three hundred years. At the climax of the game, however, the two (unintentionally) use up all the energy that made them immortal when they take control of Lares and Lemures and use them to fight the superweapon known as Tartaros. Thankfully, when Tartaros is sent back into its own pocket dimension, Lares and Lemures are permanently sent there as well, meaning that the two's purposes were served regardless, leaving them free to live their own lives like everyone else.
• Those held captive in the Well of Wonders in Sunless Skies are forced to perform in and attend to a theater play reenacting the story of a Prophet that tried to convince the Twin Kings of Eleutheria that a revolution might be a good thing. When at last the story managed to be told in its entirety thanks to your captain, they all crumbled instantly to dust, as they only had been kept alive and young to fulfill their role of reciting and hearing the complete story of the Exile Prophet. The sole exception was a little girl that became a very old woman as soon as the play ended, and died mere moments later.
• Inverted in Touhou Project with youkai, ghosts, and pretty much anything supernatural. They need a purpose to exist, so when they lose their purpose they try desperately to find a new purpose before fading away. Especially notable with the ghost Minamitsu, who has to drown people (or at least try to) in order to continue existing, even though she doesn't really have any grudge against her victims.
• In Undertale, this is what puts the "justified" in Justified Save Point. If you kill Toriel in the Ruins, and then reload to spare her, Flowey will reveal that he used to have that power himself until you fell into the ruins — apparently there's a limit of one person with this power per closed system, and you're more qualified than he is — but he did keep the Required Secondary Power of Ripple-Effect-Proof Memory. He elaborates on that toward the end of a worst-ending run, and steals it back from you at the end of a neutral-ending run. And in a good-ending run, you get a souped-up version as an 11th-Hour Superpower for the True Final Boss fight.
  • During a worst-ending run, Undyne exhibits this to a degree when you first try to kill them. Their determination towards stopping you enables them to shake off death for a Heroic Second Wind, leading up to one of the hardest boss fights in the entire game. Too bad that if you defeat her, the second death actually sticks...
  • And if you're going for the Golden Ending, the True Lab is full of failed experiments who cannot die due to being injected with Determination, which makes them immortal simply by giving them the resolve to live, no matter what.
• Wargroove: Princess Elodie of the ancient kingdom of Cacophony performed a Heroic Sacrifice to become the Barrier Maiden for an Artifact of Doom called Requiem. When Mercia and company come across her she's still 'alive' several thousand years later, albeit only as a shade of the person she once was and hellbent on keeping Requiem — and knowledge of its existence — out of everyone else's hands.

Visual Novels

• Ciel's quasi-Complete Immortality from Tsukihime is closer to this trope, functionally. The previous host-victim of the Body Surfing Big Bad Roa, she somehow failed to die when Roa's consciousness left her body, like all of his previous hosts. This turned her into a Paradox Person who is simultaneously dead and alive in the eyes of the world, which preserves her body exactly as it was at the moment she was supposed to die and instantly reverses any harm or aging it suffers. The purpose-driven aspect of this immortality came about retroactively when she made it her (un)life's mission to track down and to kill Roa, as doing so would also end her immortality (though given how Nasuverse functions, it is very much possible that the universe made one of Roa's victims into an undying assassin specifically to end his endless cycle of cheating his way out of dying).
• All the monster girls in Galzoo Island are cursed by the Big Bad to be unable to die since the Big Bad can't decide whom among the girls he should marry. It's mentioned that the curse will be lifted once the Big Bad has finally married to one of the monster girls since he has no further use for the others.

Webcomics

• In Girl Genius, the circus performer Embi made a sacred vow to see the world before he died, over 130 years ago. He takes his sacred vow seriously. The novelisation hints that this might just be a story on his part, as the members of the circus try out their skills and stories on each other. They are also all Sparks hiding in plain sight, so who knows through what science might be extending his life.
• In Raven Wolf, the title tribe was cursed with removal from the sacred circle of life until the domestic civilization is ended. This means that they stop aging at maturity and if killed, their bodies don't decompose and their spirits cannot be reincarnated until the curse ends; they also can't hunt or cultivate crops.
• Rice Boy has those chosen to seek the Fulfiller: They will not die until the Fulfiller is found (as long they keep looking). In this case, it takes around 3,000 years. Of the three seekers, one continues on the quest until it is completed, one gave up long ago and performed a Face–Heel Turn (and has moved on to other life-extending means), and the last became disillusioned with the quest itself and decided to let mortality catch up to him.
• In Tempts Fate, a B side comic to Goblins, the title character destroys a Demon who will take a thousand years to reform, after which the demon will enact revenge. However, as goblins only have a lifespan of 30 years, the demon "curses" him with immortality so that he'll still be around in a thousand years for said revenge.
• In El Goonish Shive, Abraham made a vow to destroy all the monsters the indestructible Dewitchery Diamond creates. He magically encases himself in stone (a la Human Popsicle) between incidents so he doesn't have to actually live through the intervening time.
• Marionetta: The members of the Anthonin Gremminger Traveling Troupe are immortal until they decide to leave the circus, upon which they go to heaven.

Western Animation

• DuckTales (1987): In the Five-Episode Pilot "Treasure of the Golden Suns", the character El Capitan is an elderly Spanish man. He found a golden valley (an expy of El Dorado called the Valley of the Golden Suns) but lost its location, and spent the next 400 years searching for it. He is extremely old and he looks old, but that won't stop him from keeping himself alive through sheer willpower until he finds the gold he lusts for.
• On Gargoyles, Demona and MacBeth are made immortal by the Weird Sisters as part of a plan by the Archmage to conquer Avalon. Both Demona and Macbeth agreed to become immortal (the latter also sacrificing youth to the former) in order to further their individual quests for revenge against a common foe. Appropriately enough, the terms of their immortality tie the two together in a cycle of revenge for hundreds of years. Only one can truly kill the other, ending both their lives.
• In The Legend of Korra, it's revealed that the Avatar's cycle of reincarnation was imposed by the spirit Raava in order to give him time to restore balance to the world. Apparently she has very high standards for worldly balance considering that the Avatar is still going cycle after cycle.
• Rick and Morty:
  • The Meeseeks are generated, given a single task to fulfill, then disappear, as they can't bear to exist for long periods of time. And they cannot disappear until that task is completed; they can be maimed, torn apart, et al, but they will keep going. Normally, this isn't an issue, but if they're given a borderline impossible task, such as taking two strokes off of Jerry's golf game, bad things happen.
  • Fortune cookies produced by an imprisoned alien render the eater immortal until the enclosed fortune is fulfilled. The Big Bad in the episode had a seemingly unattainable fortune (becoming the most successful businesswoman), but that didn't stop Rick from making that fortune attainable and taking her out at the same time. Rick had a simple fortune during the battle ("You will make a new friend") he hoped wouldn't happen any time soon, but Jerry instantly ruins it by calling him a friend.

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