Filth
Judgment — Uncommon
Creature — Incarnation
Swampwalk (This creature can't be blocked as long as defending player controls a Swamp.)
As long as Filth is in your graveyard and you control a Swamp, creatures you control have swampwalk.
"As the portal closed, Filth oozed through. The stench of evil followed it in." --*Scroll of Beginnings*