Oath of Ghouls | Magic: The Gathering
Formats Oath of Ghouls is Legal in
Official Oracle Text for Oath of Ghouls
Official Rulings for Oath of Ghouls
10/1/2009 : The targeted player's graveyard having fewer creature cards in it than the current player's is a part of the targeting requirement. A player can't be targeted by this ability unless it's true, and the ability will be countered on resolution if it's no longer true at that time.