Agra's Ambush

You provide protection for yourself or one willing creature against unwanted mental intrusion. The trap will be triggered if a protected creature is targeted by a spell or effect that would sense its emotions, read its thoughts, or put the charmed condition on it. The attacker must make a Wisdom saving throw. The attacker takes 3d10 psychic damage on a failed saving throw, or half as much damage on a successful one. In either case, you are alerted as to the potential intrusion.

Once this spell has been triggered, it ends.

At Higher Levels. When you cast this spell with a 4th-level or higher spell slot, the trap inflicts another 1d10 damage per slot level above 3rd.