Twin Snakes, known in Japan as Dragon Horn(竜喇叭, Ryūrappa/Doragon Hōn?) is one of Iron Fist's special moves. Empowered his legs with golden aura, Iron Fist jumps up slightly off the ground and does a double rising kick that aimed high above his head. This move is good as an anti-air attack and usually followed up by Rising Fang.
The move itself is based on Renkantai (連環腿 "Chain Loop Thigh") technique which is used by many Chinese Kung Fu-style fighter across all fighting games. Most prominently being Yun from Capcom's own Street Fighter franchise.
