Water Sprite

Trident. The  sprite makes an attack with a trident that deals 1d6 damage

Heart Sight. The sprite touches a creature and magically knows the creature's current emotional state. If the target fails a DC 10 Charisma saving throw, the sprite also knows the creature's alignment. Celestials, fiends, and undead automatically fail the saving throw.

Invisibility. The sprite magically turns invisible until it attacks or casts a spell, or until its concentration ends (as if concentrating on a spell). Any equipment the sprite wears or carries is invisible with it.