Spellcasting Variant Rules (3.5e Variant Rule)
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Alternate Spellcasting Rules
Gaining new spell levels as you level up represents your body getting more and more used to the energy that is being channeled through it by using magic. It is possible for magic users to cast spells that are higher level than they should have access to. However, doing so is costly and should only be done as a last resort. Casting a spell of a spell level higher than you should have access to is using a level of power that your body is not ready for and is harmful to varying degrees.
-To cast a spell 1-2 levels higher than you have access to, you must expend a quarter of your total daily spell slots, after which you become fatigued and lose a quarter of your total hit points
-To cast a spell 3-4 levels higher than you should have access to, you must expend half of your total daily spell slots, after which you become exhausted and lose half of your total hit points.
-To cast a spell 5-6 levels higher than you have access to, you must spend three quarters of your total daily spell slots, after which you lost all of your hit points (putting you at zero) and lose consciousness. You are exhausted and sickened upon waking up
-To cast a spell 7 levels higher than you have access to or an epic spell before level 21, you must expend your entire allotment of daily spell slots (making this impossible to do if you even used one spell), after which you die