#5 Thanatos
Thanatos has a deal with a demon named Brone, this deal allows Thanatos to use the demons powers for his own purposes, and in the end Brone will get Thanatos’s soul as payment. Thanatos’s right eye is also possessed by Brone, allowing Brone to see what goes on at all times. Thantos is practically unstopable, the only thing that could take him down would be another demon. But Brone will protect Thanatos at all costs, in order to obtain Thanatos’s soul. Thanatos has come up with a nasty habit of bringing back to dead to do his bidding. These dead are like puppets with no memory of their past life, but just alive enough to be used.