Fell Sorcery works on mindcraft spells, but it's not a huge effect (+1 spellpower if you're playing the last official release; +2 spellpower in the dev version). It also reduces your STR, DEX and CON by 1.
(One unit of spellpower is equal to 1/13 of the spell's base power/damage.)
(One unit of spellpower is equal to 1/13 of the spell's base power/damage.)
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