Aboleths

Aboleths are hulking amphibious creatures that hail from the Far Realm, a distant and unfathomable plane. They live in the Underdark, swimming through drowned crannies or creeping through lightless tunnels and leaving trails of slimy mucus in their wake. Malevolent and vile, aboleths bend humanoid creatures to their will, and more powerful aboleths can transform their minions into slimy horrors.

Aboleths

Forgotten Realms Artifact Hunters: Reassembling The Avatar of Torm Rustyham