Hilarious in Hindsight: All the complaints about Steve Reeves being replaced by Alan Steele. The real reason is that this was only made a Hercules movie in the English dub, and was originally about the Italian folk hero Maciste. The show would later do another film based on him that kept the name in the dub, Colossus and the Headhunters, where the guys legendarily renamed him "My Cheesesteak."
Padding: The sand storm sequence. One of the reasons it got trashed so much on MST3K was because it goes on forever. Though unlike the similarly infamous rock climbing sequence from Lost Continent, there are at least occasional cuts to other stuff.