Nothing screams "superhero" like regenerating body parts. It's one of the cooler things about characters like Wolverine and Deadpool. Your head is beat to a pulp by the Hulk? Grow it back already.
And it's not just the stuff of comic book fantasy. The planarian (family Planariidae) is a harmless-looking flatworm that lives in bodies of water around the globe. But don't dismiss this squirmer as nothing special, because if you were to cut off any part of the planarian -- or split it down the middle, cut it into pieces, or any other combination -- each part of it regenerates into a whole new planarian. You can take one measly cell of the planarian and it will develop into an entire flatworm, which really deserves all-caps in comic book tradition because it's AMAZING [source: Krulwich].
Even cooler? It seems to have a superpower memory. One study "taught" a planarian to be attracted to light (which they're naturally averse to). The researchers than guillotined the worm and waited for a new head to grow back. And guess what? The worm with a whole new head and brain kept the attraction to light: The new brain had old memories [source: Shomrat and Levin].