Kolthruyx the Arbiter

Indestructible, Devoid
Kolthruyx can't attack or block unless you
control three or more Spirits.
Whenever a non-Spirit creature card is put into a graveyard from anywhere, flip a coin. If it's tails,
exile that card. If it's heads, put that creature
onto the battlefield tapped under your control.
It's a Spirit in addition to its other types and
gains Devoid.