502.21b.

Objects with kicker have additional abilities that specify what happens if the kicker cost is paid. These abilities refer to whether the player who played the object as a spell chose to pay the kicker costs; they don't check what that player actually spent to do so. These abilities are linked to the kicker abilities printed on that object: they can refer only to those specific kicker abilities. They can't refer to any other kicker costs that may have been paid when the object was played. See rule 407, "Linked Abilities."