Sculkman

The Sculkman is a player-sized mob that lives in the Deep Dark.  It slouches when it does not notice you, but if a Sculk Sensor goes off in a 5-block radius of it, Its mouth opens and screeches before it runs at you.  It has the speed of a Villager.  

Achievement: Kill the Warden, Then all the Sculkmen shake and turn into Villagers.

Damage: 5-7

Health:  20