Skarda, Dredge Lord

Flying, swampwalk
When Skarda, Dredge Lord enters the battlefield
you may exile all graveyards.
{b/g}{b/g}{b/g}Sacrifice a creature: Return target
permanent exiled by Skarda, Dredge Lord
to the battlefield under your control, if it is a
creature it becomes a black zombie
in addition to its other types.