Lord of Extinction

Lord of Extinction's power and toughness are each equal to the number of cards in all graveyards.

Entomb

Search your library for a card, put that card into your graveyard, then shuffle.

Yargle and Multani

Stitcher's Supplier

When this creature enters or dies, mill three cards. (Put the top three cards of your library into your graveyard.)

Filth

Swampwalk (This creature can't be blocked as long as defending player controls a Swamp.)
As long as this card is in your graveyard and you control a Swamp, creatures you control have swampwalk.

Coram, the Undertaker

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.

Brawn

Trample
As long as this card is in your graveyard and you control a Forest, creatures you control have trample.

Anger

Haste
As long as this card is in your graveyard and you control a Mountain, creatures you control have haste.

Kethek, Crucible Goliath

At the beginning of your end step, you may sacrifice another creature. If you do, reveal cards from the top of your library until you reveal a nonlegendary creature card with lesser mana value, put it onto the battlefield, then put the rest on the bottom of your library in a random order.