Goofs

The real Colosseum could hold an estimated 50,000 (or more) people. In this film, it appears to hold only a few hundred.

Various scenes in the palace feature Vitellius ("Caesar" in the American version) and others drinking wine from brass goblets. It's obvious the goblets are empty; the characters gesture with them freely without spilling a drop, and at times offer views clear to the bottom.

Man visible in gorilla suit, which also has sewing lies visible in several places, and the man's eyes and skin surrounding his eyes are clearly visible behind the poorly-crafted gorilla mask.

In the U.S. version titled "Terror of Rome Against the Son of Hercules" Maciste is renamed "Poseidon" even though he has nothing to do with that Olympian god.