A true mage is a master of the essence of his craft, be it fire, lightning,
cold, or many. This essence allows such true spellcasters to push the limits
of what a sane caster would attempt. A little insanity, however, lets the
caster push even further, but at some personal risk. Use of this skill in
combat can greatly improve the chance of mage essence, but can cause the
spell's effect to leak onto the caster as well when it is released.