Robot Jox (1989)

Revealing mistake: When the main guy is fighting the main girl in his room, the scene changes angles and you can CLEARLY see that her stunt double is a man!

Achilles: You're making my beer curdle.
Alexander: And you make my drink taste like blood.

Achilles: You can live.
Alexander: Yes, if I kill you with this.
Achilles: We can both live.
Alexander: We are already dead. We are Robot Jox.