Roy KOing Struve.
JDS KOing Werdum.
Hapa KOing Struve.
Carwin KOing Mir.
Cain's pure destruction of Rothwwell,Bigfoot and Lesnar.
Overeem's beatdown on Brock.
Kharitonov KOing Overeem.
Though I agree those were great fights and some great KO's, what I mean by "big man" is someone huge who have to cut down to 265lbs, who was knocked out by a great strike
Overeem was a bulked up 205lbs fighter when he was beat,
Mir is probably right at the limit and doesnt have to cut
Struve is not even 265lbs, even though he's as tall as a skyscraper
Cain beat the hell out of all these fighters, but did not KO them
Following: Cain , JDS, Werdum, Shogun, Machida, Weidman, Pettis, Aldo, Melendez