Boon of the Apex Spell Caster (5e Epic Boon)
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Boon of the Apex Spell Caster
After reaching the apex of spell casting, you've gained insight into the truest understanding of how to weave the magic of the universe into your spells. You gain the following benefit:
When you cast a spell of 2nd level or higher, you draw on the surrounding magic infused in the universe to aid your casting. Roll a d20 and subtract your spellcasting ability modifier, if the result is less than 0, you do not expend a spell slot for casting that spell. You can only use this once for each school of magic between long rests. If you roll is equal to a 0 or a 1, you can use a spell slot that is 1 level lower than the spell slot you are attempting to use, however, you must have that spell slot in order to gain this benefit.