Swarm Trap

You touch one closable, inanimate item and designate a password. If someone opens the item without saying the password, the item releases a swarm of mosquitos.

Each creature within 10 feet must make a Dexterity saving throw. A target takes 4d6 poison damage on a failed save, or half as much damage on a successful one. The item itself takes no damage from this spell.

At Higher Levels. When you cast this spell using a spell slot of 4th level or higher, the damage increases by 1d6 for each slot level above 3rd.