The Slimeslug is a slug like slimy creature with one eye, they move by inching its way, They're encountered in Caves, Mangrove Swamps and Plains.
These can't split up after death unlike Hopping Slimes.
They have multiple versions, The Bloodslug, The Alienslug, The Icyslug, and The Magmaslug.
Due to Issues with Caseoh (Notch, The Ugly Former Developer of Minecraft who is a transphobe and neo nazi), They became what we know Today, Same Reason for The Stalker and Its Versions.