Corrupt Spell

As a reaction when another person or creature casts a spell you can reach out and take control of the spell. Roll a d20+ your spell casting modifier and your proficiency bonus. The DC is 12 plus the spells level.

If you succeed you take control of the spell.

If the spell targets a individual you can change the target to a creature of your choice.

If the spell targets an area you can decide the area. 

If the spell summons a creature it acts as if you summoned it. 

If the spell requires consention it uses your consentation.

For spells that have a duration the original spell caster can make a saving throw (dc = 12 + spells level) using their spell casting ability to regain control of the spell.