But think of it this way. Ki is energy, he's been killed by beam energy, and then he's already been beat by that guy that was made of life force from that planet that is in Hunter/Prey series, and life force is exactly what Ki is. So any blast would be nullified. However Gokou's skin isn't as durable as Supes, and the bone knuckles went thru Supes biometric filed, and all plus when he had mother box helping him out. They are posionus, and Gokou isn't immune to poison.
Actually Gokou has since he can be cut, and stuff. He's not been killed from being shot but he's also been shot..tho he was much younger. And then Gokou gets hurt when knocked into the mountain, and also he's been hit with blast that have hit the ground, and not done much but make a big hole, where as I've seen Supes been knocked farther, and survived a blast that made miles, and miles as smooth as glass, and was only dazed...Which was alot more then what Doomsday was who wasn't effected at all.