Gloglablyn
Yes I know about Mas Oyama the Legendary "Godhand" who killed someone with one punch. (He did! the records prove it!) A good website to know more is Fighting master, just google it and it should appear. And also he fought many bulls not just one and killed three instantly. I know it sounds cruel but they let him do it because were going to be slaughtered anyways, though I still find it disheartening he did not do it out of spite or pleasure, he wanted to pit his skill and strength in an ultimate battle involving man against beast.
It was NEVER proven to be one punch. I mean, records prove Rickson Gracie has a 400-0 records. And I believe he admitted to the fact that ALL the bulls he fought were drugged and basically put in a position where as long as you can side step you could probably kill it. Considering they were pretty much dead when he fought them.
Mas Oyama actually disliked Japan for resenting his Korean background. Kinda odd. Same thing with Rikidozan.
Rikidozan is another legend. Albiet a Pro-wrestling legend.
He did knock out Kimura though. Although it was gay how he did it. It was suppose to be 3 matches. end with it 1-1-1. However, Rikidozan did not want to do this and pretty much just kicked kimura in the face with a steel toed boot, after he had hit Kimura on his back, or back of the head (can't remember which) force him to go down halfway. After this, many people did not like rikidozan. Eventually he was stabbed to death by Yakuza after going back on some kinda deal.
all in all. Kimura > all 3 of them.