Headbutts, groin strikes, strikes to the back of the neck & head, kicks to a downed opponent, small joint manipulation, and hair pulling all became officially illegal.
The historical Hellcat Maggie used to file her teeth down to sharp points and wear brass fingernails for combat, and Sadie the Goat had a habit of headbutting unsuspecting men on the streets in the stomach so her followers could rob them.
The 2006 book La mélancolie de Zidane (Paris: Minuit, 2006) is a lyrical essay on the headbutt administered by the French football player Zinedine Zidane to the Italian player Marco Materazzi during the 2006 World Cup final in Berlin.
Burmese Lethwei, a traditional Burmese martial art of which has now grown into a popular kickboxing event with strong emphasis on knee, elbow strikes and headbutt.
He defended the belt once against Ric Magramo before losing it to Jacob Matlala, after Weir was unable to continue due to a deep cut from an accidental headbutt in the fifth round.
Forced to adapt, he begins using a new style mixing in elements of grappling, dirty boxing head-butts and elbows, wrestling, and wu-shu.