The Snail Creatures (Snailbies) are snails with human-like limbs. They have large, sideways mouths on their face and move incredibly slow. Although a singular Snail is not dangerous, they can travel in large groups.
Despite rumors that they're quite rare, they're actually pretty common in the Old World.
If you get caught by one you can sprint away from its grasp. Just be careful as to where you're running so you don't wind up in danger.
Snail Creatures can be spawned by the Snail Spawner or by the Snail Lord.
The game's files refer to it as "Zombe."