Sea Snail

The Sea Snail is a rare enemy that spawns in the Ocean on either end of the world, usually during the night. Even then the spawn rate is still the lowest of all enemies in the Ocean, one third that of Squids. It slowly crawls along the sea floor.

When killed, it drops Purple Mucus, which is used to craft Purple Dye at a Dye Vat.

Trivia

 * It closely resembles the (commonly known as Australian trumpet or false trumpet), the largest extant snail (shelled gastropod) species in the world, and the largest (heaviest) gastropod in the world.
 * The sea snail was used to create purple dye, it was so rare that its value was its own weight in gold. This is also why no country has purple in any of their flags.