Who Needs Their Whole Body?

So yeah, I just killed this huge guy over here. How, you ask? By chopping him in half with my BFS! Surely, No One Could Survive That! But wait, what? What do you mean, part of him is getting back up?! What the hell does it take to stop this guy?!

Who Needs Their Whole Body? is basically when a sentient being is able to function without their entire body in one piece. The portion of the being that's still functioning is often quite frightening to look at. In most cases it takes a hit to the brain to actually stop it, but there have been cases where even that doesn't work.

Frequently overlaps with Organ Autonomy. When this happens with someone's head, see Losing Your Head. When this happens in a video game, it's usually a case of Didn't Need Those Anyway.

See also Pulling Themselves Together, for when they did want that part back.

Examples of Who Needs Their Whole Body? include:

Anime and Manga

In Princess Mononoke, Moro's severed head manages to jump up and bite Lady Eboshi's arm clean off.
In Dragon Ball and its successor series:
- Sgt. Metallic was a robot who was able to keep fighting even after his head and hands were destroyed, only stopping when his batteries ran out. Since he was a Shout-Out to The Terminator, that's not surprising.
- Frieza ended up getting in the way of his own attack and losing the lower half of his body and an arm. (see the image links page) At first, it doesn't seem like this trope is in effect. He isn't outright killed, but he can't even move. Once he gets a little bit of a power recharge, he suddenly he doesn't seem to be that worried about half of his body being gone. Later on, he gets cybernetic replacements for his missing parts.
In Franken Fran, people upgraded with regeneration tend to do this when bisected. In one case Fran herself cut her bottom half off when her hips didn't fit in the ventilation duct she needed to escape through. She survived through, being ambiguously undead.
Black Claw in Re: Cutie Honey is all over the place with this one. First she's decapitated, and her body gets up and keeps fighting while her head continues taunting the protagonist. When she feels her body needs the power boost form her head again, she reattaches it, only to be bisected vertically. Her two halves have a brief conversation afterward.
Battle Angel Alita is rather notorious for this, once letting a foe slice her arm off at the shoulder so she could overcome a reach disadvantage with the resulting impromptu club.
Hisoka from Hunter X Hunter lets an arm get cut off for fun one time, too. He then swings it around on invisible sticky energy string for a while, and then patches it on with camouflage energy sheets and pretends it's reattached before playing with the guy a little more and then losing interest. Then he goes away, calls a specialist to sew his arm back on with energy microfilament, and has a shower.
- From the same author, the elder Toguro brother in Yu Yu Hakusho gets blasted down to about half of his head, first by Kuwabara owning him and then by his little brother exploding. He's weakened, but still perfectly lucid.
In a particularly disturbing moment in Moldiver, one of Doctor Machinegal's gynoids crawls away from Mirai, spine and synthetic organs hanging out, after being torn in half.

Comic Books

In Stormwatch: Team Achilles, a gynoid taunted her attacker who had shot her in the head: "I don't keep my brain there, you idiot! It's in my chest surrounded by inches of diamondsteel!"
In the Batman comics, cyborg foe Gearhead has been shown crawling after Batman (or away from him) with most of his robot body destroyed.

Film

Prince of Darkness. The woman who becomes The Chosen One of Satan has her head cut off. She picks up her head and puts it back on her neck, where it re-attaches itself.
A T-600's upper half attacks John Connor in Terminator Salvation and doesn't stop attacking him until he completely redecorates its face using a machine gun. Justified because it's a robot.
- Also happened with the T-800 in the original Terminator after Kyle Reese blew its legs off with a pipe bomb.
Gmork the werewolf does this in The Neverending Story.
The Black Knight from Monty Python and the Holy Grail simultaneously plays this straight (he's still alive with injuries that would normally be fatal almost immediately) and subverts it (not very threatening anymore, what?)
The 2010 remake of Clash of the Titans has a hand which changes into a giant scorpion.
Knights by Albert Pyun has Gabriel getting blown in two. Played with in that he just crawls over to another cyborg's corpse and chops its legs off for spare parts.
Bishop in Aliens.
The Bug in Men in Black.
Used as a Jump Scare in the 2004 remake of Dawn of the Dead, while the mall security guards are checking around the mall's garage, a legless zombie clinging to the rafters brings down one of the men.
Happens in Beyond Re-Animator to an unfortunate Jerkass zombie-turned prison inmate, who continues his un-life as a bloodied torso.
Braindead / Dead Alive has several instances; the disembodied organs of a biker punk crawl around for half the movie menacing people, and the top half of a zombie's head manages to threateningly roll his eyes until someone sticks him in a blender...

Literature

The Zombie Survival Guide warns that disembodied zombie heads are still a danger, and need to be destroyed completely.
Harry Keogh, Brian Lumley's titular Necroscope, can call the dead out of the ground to fight for him, and does so on several occasions. When the dead are destroyed, even the blown-off arms try to crawl into the enemy positions and strangle the gunners.

Live-Action TV

Doctor Who: The battered Cyberman from "The Pandorica Opens" does most of its attacking with a disembodied head and arm. The head also reattaches.
- There was also Cassandra, who was born a normal human with a body, but by the time the Doctor encountered her had been reduced to a face in a blob of stretched out skin.
- And Ursula from "Love and Monsters", who ends up as a face in a block of concrete.
In Living Color had "The Head Detective", a series of skits about a cop that was badly injured and had to undergo amputation... of everything except his head (with little plastic feet and hands stuck on.)
Angel once went up against a demon that kept piecing itself back together and attacking no matter how many times he chopped him in half.

Angel: Come ON! I'm holding your head!

The 'Bicycle Girl' half-zombie, complete with trailing entrails, in the pilot episode of The Walking Dead

Oral Tradition, Folklore, Myths and Legends

The Green Knight of Arthurian legend let Gawain cut his head off, picked it up and left carrying it.

Tabletop Games

Dungeons & Dragons.
- Iron golems could continue to function after losing their heads, including breathing out poison gas.
- Module I6 Ravenloft. When Strahd zombies had their limbs cut off, the limbs could continue to attack.
- More generally, constructs (like golems) and most undead (aside from vampires) can survive decapitation, and anything with multiple heads (like hydras) can survive losing any head but the last one. Creatures with the Regeneration ability (like trolls) can grow back lost body parts or even reattach them by holding the severed limb against the stump. Many oozes have the Split ability which causes certain attacks to divide them into a pair of identical oozes just as formidable as the original except with half the hit points.

Video Games

The Mgalekgolo/"Hunters" from Halo. Justified because they're made up of thousands of Lekgolo/"Worms" all working together to create a large "body" designed for fighting.
Some pictures from Warhammer 40,000 show damaged Necrons crawling on their hands just like the T-600 in the picture above. Since their regeneration special rule is called "we'll be back", it makes perfect sense.
In MadWorld's Mad Castle stage, the common Mooks are zombies. If you want to cut them up, be sure to bisect them; cutting them in half at the waist won't put them away, and eventually they'll even regrow the bottom half.
Cyborg units in Command and Conquer: Tiberian Sun will lose their legs once most of their health has been lost, but still function, albeit with reduced movement speed. They're still healed by tiberium, but it won't make them grow their legs back.
Necromorphs from Dead Space, who can often function without their legs, or heads.
Killing a zombie in Half Life 2 by launching a sawblade at the torso with the gravity gun sometimes doesn't kill it: the zombie's upper torso will keep coming after the target. Conversely, killing a zombie with anything except fire or a headshot has a pretty high chance of the headcrab detaching itself from the corpse to find a new host.
Zombies in the Resident Evil series have been known to do this. There's a notable instance in the second game, where you blow a zombie in half with a shotgun and the top half keeps crawling towards you.
Some of the zombies in Diablo III will turn into crawling torsos when damaged; some of them start off that way.

Web Original

Splatterman, from the Global Guardians PBEM Universe, has a Healing Factor that works so quickly it makes Wolverine green with envy. He lost both his legs an arm, and half his torso to a supervillain once, but kept crawling after the guy as his body regrew itself.

Western Animation

The second series of Star Wars: The Clone Wars introduces a Geonosian hivemind so powerful that it can maintain strong connections with its warriors, living or dead. This includes the warriors that have otherwise fatal wounds to their bodies - you can shoot it with laser guns or chop it up with a lightsaber, but it'll keep coming for you.
Men In Black: The Series: the clone of a Mad Doctor.