Werthrent

Werthrent is a demonic gigantic fire serpent worshiped on Ash's homeworld and serving as the main antagonist of Final Space episode, "The Grand Surrender".

Appearance
Werthrent is a massive, black snake-like being with fiery golden rings on the body, glowing red eyes, sharp teeths and nostrils like a bat.

History
At some point in a past, Werthrent left his dimension and arrived on the planet Serepentis where the locals accepted him as a deity. Serepentians regularly make sacrifices for him, because they believe that the chosen ones will go to another world and be eternally happy, however, swallowed victims, once inside the pocket dimension of Werthrent, their minds are exhausted, turning them into zombified agonizing slaves who have been suffering pain for a lifetime and eternity.