The Amazing Colossal Man (1957)
Lt. Col. Glenn Manning is inadvertently exposed to a plutonium bomb blast at Camp Desert Rock. Though burned over 90% of his body, he survives, and begins to grow in size. As he grows, his heart and circulatory system fail to keep pace with his growth, and he is gradually losing his mind as a result of reduced blood supply to his brain. He reaches 50 feet tall before his growth is stopped. By this time he has become insane. He escapes and wreaks havoc upon Las Vegas before he is finally stopped. Written by Teresa E. Tutt
Who hasn't lost big time in Las Vegas and wanted to wreak havoc? (I'm just saying.)
Also, it's unlikely Rifftrax would get the rights because even Shout! Factory in all their glory couldn't get the rights to the MST3K episode.
What is with people requesting already MST'd episodes??????
STAR WARS STINKS commented
This was an episode of MST3K.