Giant Worm

The Giant Worm tunnels through the Underground and Cavern Layer in search of it's prey. It'll pop out at spots in the ground near you, but you'll hear it (it makes a steam-train like sound), so be careful. These things get annoying fast, so aim for the head for a quick kill. Giant Worms follow the Worm AI. Giant Worms also have a very rare chance to drop a Whoopee Cushion, an accessory that provides 2 Defense.