Tombstalker | Magic: The Gathering
Formats Tombstalker is Legal in
Official Oracle Text for Tombstalker
Delve (Each card you exile from your graveyard while casting this spell pays for .)
Official Rulings for Tombstalker
6/7/2013 : If you sacrifice permanents or discard cards while casting the spell (for example, activating the mana ability of Blood Pet), those cards can be exiled using delve to reduce the spell's cost.