Underworld Animal Heads Picture

Just thought of an idea dealing with ancient mythology, if their is a large beast called a Cerberus (dog with three heads) what other beast may be down there? So the one on the left looking to the right is a horse like beast with reptile features and the one on the right looking to the left is part rhino and reptile.
Hades, King of the Underworld
Underworld Animal Heads
Hades - God of the Underworld