Ground Seal | Magic: The Gathering
Formats Ground Seal is Legal in
Official Oracle Text for Ground Seal
Cards in graveyards can't be the targets of spells or abilities.
—Seton, centaur druid
Official Rulings for Ground Seal
7/1/2012 : Only spells and abilities that target cards in graveyards will be affected. Abilities that don't target cards in graveyards (like the one Tormod's Crypt has) can still affect those cards.