Merasmus, Idiot in a Dress

Hexproof
Creatures you control can tap to add mana of any color in your commander's identity.
The Necromancer of No Refunds —Swap the power and toughness of one target creature. If it dies this turn, create a black 3/3 Ghost creature token with flying and shroud. Repeat this for every creature that dies this way.
{u/b}{u/b}{u/b}{u/b}{u/b}: Create a copy of a creature in any graveyard. It becomes a ghost in addition to other creature types with flying and shroud.