Deliberate mistake: When Kalidor beheads a warrior and when Sonja beheads the wizard, both heads don't fall sideways as they should, but instead fly upwards, revealing they were tossed by someone offscreen - which looks more impressive, indeed.
Red Sonja (1985)
1 deliberate mistake
Directed by: Richard Fleischer
Starring: Arnold Schwarzenegger, Brigitte Nielsen, Sandahl Bergman, Paul L. Smith
Revealing mistake: When Varna is sliding down the rope and gets shot in the back with an arrow, the safety pad under her clothes protrudes noticeably.
Brytag: I will tell the future in your entrails, Red Woman.
Red Sonja: I know my future. You have none.