Locket of Yesterdays

Text:

Spells you cast cost less to cast for each card with the same name as that spell in your graveyard.

Rulings:

• 9/25/2006 Locket of Yesterdays reduces only the amount of mana you need to pay to cast a spell. The spell’s mana cost and converted mana cost are not affected.
• 9/25/2006 Colored costs can’t be reduced by this effect. For example, a spell that costs <img src="/Handlers/Image.ashx?size=small&amp;name=2&amp;type=symbol" alt="2" align="absbottom" /><img src="/Handlers/Image.ashx?size=small&amp;name=R&amp;type=symbol" alt="Red" align="absbottom" /> can’t be reduced by more than <img src="/Handlers/Image.ashx?size=small&amp;name=2&amp;type=symbol" alt="2" align="absbottom" />.
• 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.