Hades didn't create the Underworld, he simply became it's ruler.
No. Pluto is the name of the Roman version of Hades.
Hades has the power to rule the Underworld and also request animals, including humans, to be killed.
Prayers to Hades were often carried out with banging on the ground to be sure Hades could hear you. The sacrifice of black animals was also common.
His Three Headed Dog Was Cerbues
he created the underworld , and he created the male body parts
I would say Cerberus. But, he is fond of black animals.
No, Thanatos is the son of Nyx and Erebos, primordial Gods that pre-date the Olympians.
He created the animals.
you can create several, but if you mean for that one level where you create 3 animals with certain characteristics i did bat, lionfish, and snapping turtle.
Hades and Persephone have no children. From what I have read, if they did have any children, they were mostly monsters and such. I guess it made sense... Why should the God of Death be able to create life?
Yes, he can reincarnate himself into different (fearsome) animals by hades side but he generally is not slain by heros.