Skulker, a Deep Dark Shulker

In the Deep Dark, some blocks could actually reveal to be mobs hiding, called Skulkers. A sort of Shulker variant, they are blind like the warden and have ultraviolet blue skin under their shell, with sensors on top. If they detect the player, they reach out with a long vine or possibly a large spore like a shulker bullet with more wobbly movements which sways from side to side. The player must carefully move around this, as if they get hit they receive an effect called ‘Jinxed’, causing them to visibly tremble and occasionally move a step in a random direction, as well as taking damage. This makes it very difficult to avoid the Warden. Rather than teleporting, they can bounce like a slime from the floor to a wall or ceiling if uncomfortable.