Sea Serpent

The Sea Serpent is an enemy that crawls around in dark places. If you throw pikmin on top of it, the pikmin will hit it once and run back to you. If you swarm the serpent, the pikmin will stay on it, but they won't deal as much damage and some of them will most likely die.

Olimar's Notes
I don't like snakes. The easiest way to kill them is to throw pikmin on top of it. I had to learn that the hard way...