The Wretched

The Wretched has advantage on an attack roll against a creature if at least one of the Wretched's allies is within 5 feet of the creature and the ally isn't incapacitated. The Wretched otherwise has disadvantage on attack rolls.

Melee Weapon Attack: +3 to hit, reach 5 ft., one target. Hit: 6 (1d10 + 1) piercing damage, and the Wretched attaches to the target. While attached, the Wretched can't attack, and at the start of each of the Wretched's turns, the target takes 6 (1d10 + 1) necrotic damage.

The attached Wretched moves with the target whenever the target moves, requiring none of the Wretched's movement. The Wretched can detach itself by spending 5 feet of its movement on its turn. A creature, including the target, can use its action to detach a Wretched.