Behemoth

A Fiend fought in Chapter 8: Final Chapter, of which it is the primary antagonist. It is the final boss, and can only be accessed if you have killed all other Fiends. You receive your right arm for killing it.

Description
The Fiends created Dororo using Hyakkimaru's body parts. The Behemoth was the Fiend that lived in Dororo and was charged with the task of guarding all the 48 body parts.