: Destroy target artifact if its converted mana cost is equal to the amount of unspent mana you have.
12/1/2004 The artifact’s converted mana cost must be exactly equal to the amount of mana in your mana pool when the ability resolves. If there’s less mana or more mana, the artifact won’t be destroyed.
12/1/2004 The mana has to be in your mana pool before the ability resolves. The ability doesn’t allow you to activate mana abilities while it’s resolving.