Starfish are incredibly cool animals. Not only can they regrow a complete limb if lost, but they also have two separate stomachs. Most of them eat by ejecting their cardiac stomach (the one directly connected to their mouth) onto their prey and then partially digesting them. Some species of starfish are even able to inject their cardiac stomach inside a mollusc shell, essentially eating the clam or mussel alive.
And beyond those cool things; they have millions and millions of tiny tube feet they use to move around and recognize prey as well as predators. If you had never heard of starfish and read some piece of genre fiction around these creatures, would you believe they exist?