Ardboys are the thunder before the storm — mobs of scrap-armoured orruks who march to the boom of war-drums and crash into enemy lines like a rockslide that has learned to walk. What they lack beside their Brute betters in sheer size, they make up in stubbornness: an Ardboy mob holds ground the way an anvil holds still.
Every Ardboy is an orruk with ambitions, because orruks grow with victory and every scar is a rung on the ladder. Fight well and long enough, and an Ardboy earns the mass and standing of a Brute; die, and at least the drums played loud. Between those two outcomes lies the whole of Ardboy philosophy — which is why they sing on the march and laugh in the shield-wall.