Locket of Yesterdays | Magic: The Gathering
Formats Locket of Yesterdays is Legal in
Official Oracle Text for Locket of Yesterdays
Official Rulings for Locket of Yesterdays
9/25/2006 : Colored costs can't be reduced by this effect. For example, a spell that costs can't be reduced by more than .
9/25/2006 : The spell being cast doesn't reduce its own cost, even if you're casting it from a graveyard. At the time the cost is reduced, the spell is on the stack.