If Borgut fights in a challenge, then at the beginning of the first Close Combat phase of the challenge, he can smash his thick Orc skull into the face of his opponent. This is in addition to his normal attacks, and is resolved before any other attacks in the challenge. If this attack inflicts an unsaved Wound, the target is reduced to WS 1 and gains Always Strike Last for the rest of the Close Combat phase. If this mighty 'eadbutt kills his opponent, Borgut can still make his remaining attacks to calculate overkill for the purposes of combat resolution.