Marvel Super-Heroes #64

Ka-Zar and the Hulk battle as the jungle lord tries to figure out a way to get him to turn back into Bruce Banner in time to stop an alien machine from destroying the Earth using deadly weather patterns. Ka-Zar is captured and taken by the Swamp Men to be a human sacrifice for the giant creature known as Umbu. Hulk fights Umbu but transforms back into Banner thanks to a fortuitous gas attack. Banner races to stop the mysterious Earth-destroying machine with Umbu close on his tail and trying to stop him. Banner succeeds but is killed in achieving his victory.