how do u destroy the power relay?
just hold down normal melee attack. You also need to be level 3 monster.
EDIT: Yes, there is a damage indicator.
Hold down attack button (left click on pc) while in front of it. Your monster will go into an attack animation.
You hit it as the stage 3 monster.
I tried. I was just wondering cause I didnt see any change. there should be a damage indicator for that thing.