Creeper

Charged. If the creeper takes lightning damage and survives, it becomes charged. If charged when it explodes, the damage dealt is doubled

Silent Steps. The creeper's footsteps make no sound, regardless of the surface it is moving across. The creeper also has advantage on Dexterity (Stealth) checks that rely on moving silently

Explode. The creeper may use this action to ignite itself and explode at the start of its next turn as long as its intended target is still within range. The explosion kills the creeper and inflicts bludgeoning damage upon any creature or object within a certain radius. The damage inflicted depends upon how close the creature or object was to the explosion

1-5ft = 4d6 + 3

10ft = 3d6 + 3

15ft = 2d6 + 3

A creature may attempt a DC 13 Dexterity saving throw to instead take half damage.