Quote from utger2722
maybe you could add in hades so he could be in the nether and have cerberus guard him. After you kill cerberus then you could fight hades and he could be able to shoot skulls and dark balls of death. when you kill him maybe he could drop a dark gem so you could summon cerberus to fight for you or be able to do what hades does.
Oh great now i have to make a Hades