I've always enjoyed the various designs of ExDeath and the concept of him. He's basically like Naraku from Inu-Yasha in that he is an amalgamation of hundreds if not thousands of demons and evil magic merged together by the holy tree they are sealed within. It's why his Neo-Exdeath form is so cool because it's basically his soul coming apart as all the various creatures that make him up are coming undone by the void.

neo_exdeath_by_despear.jpg