Arcane Reflection

When damaged by a spell from a source you can see, you can cast this spell as a reaction. Roll a D20 and add your Spellcasting ability modifier,  (DC = 10 + the opponents Spellcasting ability modifier) on a success you reduce the spell’s damage by half and reflect the damage you ignore back at the caster; on a failure the spells damage is just reduced by half.

You must cast this spell before the damage is rolled.

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