Prerequisite: Swarm subclass, Warlock level 6

When you hit a creature with your swarm attack, you can attempt to grapple it using your spell attack modifier in place of your Athletics skill. While grappling a creature as a swarm, you occupy all of its space and only its space, your movement is reduced to 0, the creature's movement is not affected, and if the creature moves you move with it.

When a creature you are grappling starts its turn, it takes damage equal to your Charisma modifier. This damage can be of any type that you can deal with your swarm attack. The grappled creature can use its action to escape the grapple as normal.