Turpin

Turpin Mushrooms: The Turpin mushroom is another favorite of magic users. It functions like Mirget leaves and Luffin flowers, in that it stays "In use" until it releases its effect. When a magic user wants the next spell cast to have its maximum possible potency, he or she will be sure to use a Turpin before the spell is cast. Useful not only in combat, the Turpin's effect will maximize the damage of a cantrip, or the power of the caster's next Fireball.
Property:  All variable, numeric effects of your next spell are maximized. Saving throws and opposed rolls are not affected, nor are spells without random variables. A maximized spell uses up a spell slot three levels higher than the spell’s actual level.