Cloak of Serpents

A mass of writhing, translucent snakes drapes your body, protecting you from harm and fending off enemies. You can end the spell early by using a free action to dismiss it.

For the duration of the spell, you gain resistance to poison damage and immunity to the poisoned condition. In addition, whenever a creature within 5 feet hits you with a melee attack, that creature is struck by one of the serpents. The attacker takes 2d8 poison damage and must succeed on a Constitution saving throw or be poisoned for 1 minute. A successful saving throw halves the damage and negates the poisoned effect.