The wearer has the option to double the base damage (including the extra damage from passing the planar skill check, but no other bonuses) of a cast Spell (excluding any scrolls or “as a scroll” effects), but when doing so the caster suffers 25 points of Eldritch damage. It’s only usable once per round, but other than that it may be used as often as desired. Mad Evoker’s Charm (MEC) must be activated before casting the Spell,