Glaucus atlanticus (commonly known as the sea swallow, blue angel, and blue dragon) is a small, blue, pelagic sea slug. As I discussed in my post on why gastropods are awesome, this nudibranch can feed on cnidarians (like jellyfish) and harvest their nematocysts (stinging cells)—so this gorgeous slug not only looks like a Pokemon, but it can actually copy other creatures' moves!
