Cracks in the Armor

As you trace arcane runes in the air and mutter the words of incantation, you are able to see the multitude of weaknesses within a foes defenses. The target must make an Intelligence saving throw against your spell DC to avoid your penetrating gaze from revealing all. On a failed save, the target is vulnerable to all bludgeoning, piercing, and slashing damage as you cause the weaknesses in its defenses to glow brightly, showing others exactly where to attach to do the most harm, for the duration of the spell. The target may make a saving throw at the start of each of its turns to end the effect of the spell. No effect on a successful save.