Gunhead Martial Arts (ガンヘッド マーシャル アーツ Ganheddo Māsharu Ātsu?), or G.M.A. for short, is a fighting style developed by the Battle Hero: Gunhead, and used by himself and Ochaco Uraraka, who learned this martial art during her Hero Agency Internships with him.
The G.M.A. is designed for close-quarters combat and self-defense, that prioritizes grappling, grabbing and hold techniques. The objective of this fighting style is to cause the submission of the opponent as soon as possible, using for this purpose several movements to immobilize, neutralize and facilitate their capture. It also has techniques that allow the quick disarmament of the adversary if they carry a weapon.
Ochaco Uraraka has become an expert in this martial art, developing a few moves that she is able to use in conjunction with her Zero Gravity Quirk. This could be seen in her fight against Himiko Toga, where she slamed Himiko's head into the ground and took her knife away. Similarly, Ochaco manages to take by surprise and subdue Neito Monoma during the fifth round of the Joint Training Battle.