Parallectric Feedback

Izzet League Spell
Level 3
Casting Time: Reaction
Duration: Instantaneous
Range: 120 (?)
As a reaction to a spell you can see being casted within range, the creature that is casting the spell that was reacted to makes a Dexterity Saving Throw or takes 4d6 Lightning Damage. This damage does not count towards concentration as it takes place before the spell resolves.