Coram, the Undertaker (Extended Art) (M3C-027) - Modern Horizons 3 Commander: (Extended Art)

Coram gets +X/+0, where X is the greatest power among creature cards in all graveyards.
Whenever Coram attacks, each player mills a card.
During each of your turns, you may play a land and cast a spell from among cards in graveyards that were put there from libraries this turn.