Gokudô Heiki plot
"Try me."
Shozo Iwaki, an ex-yakuza and currently a mercenary in South America, learns that his father Kenzo, also the leader of the Iwaki gang, has been murdered. He returns home after 4 years to find that Kurawaki, his father's number one, has committed treason and killed Kenzo. Shozo is out for revenge. After an epic battle, Shozo and Kurawaki are left for half-dead, with Shozo losing an arm and a leg. Despite his serious injuries, he survives and awakens in a mysterious medical service with an M61 Vulcan cannon where his right arm used to be and a rocket launcher where his left leg was. Shozo, a bit surprised at first, likes his new armored body and prepares for a revenge match against Kurawaki, who has also undergone some mechanical improvements. But first, Shozo will have to deal with Tetsuo, his former best friend who was now enlisted by the Kurawaki gang to kill him...