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 or any monstrous mount they may be riding (note this does not include steeds). This is in addition to his normal attacks, and is resolved before any other attacks in the challenge. If the attack hits, it is worked out at Strength 7 and if the recipient of Borgut's 'eadbutt suffers a wound then he/she/it counts as WS1 for the rest of the Close Combat phase and will attack last, regardless of charging, magic items or any other bonuses. If this mighty 'eadbutt kills his opponent, Borgut should still make his remaining attacks to calculate overkill for the purposes of combat resolution.