You are trained to take advantage of spellcasters while they are distracted by their own spells.

Prerequisite(s): Int 13, sneak attack class feature

Benefit: When you attack an enemy who is casting or concentrating on a spell of a level equal to or less than the number of sneak attack dice you possess, you gain a bonus to your attack roll equal to the number of sneak attack dice, to a maximum of +5. (e.g., 3d6 sneak attack grants +3 to attack if the spell is 3rd level or lower, while 7d6 sneak attack grants +5 to attack if the spell is 7th level or lower.) The attack does not need to be a sneak attack for the bonus to apply. You gain the same bonus to Stealth checks made to hide from opponents who are concentrating to maintain spells (regardless of spell level).