Cinematic Confusion

This is probably the most egregious example of a PEPLUM title that doesn't make any sense, vis a vis the movie or mythology itself, and how badly marketed it was here in North America.

The original title for this film is MARS - THE GOD OF WAR starring Roger Browne as Mars. Venus barely figures in the original storyline and yet for the US market, they got rid of Mars and pronounced him as the Son of Hercules (Mars the son of Hercules?) and have him pitted against...Venus?

If that's not confusing enough, the two figures on the cover of this VHS tape don't even look like the main actors and it certainly doesn't even look like anything in the film (the man is obviously a copy of Steve Reeves). I know it's marketing and no one renting the film knew or cared about the actors from the 1960s but if they had to change the look to sell it to younger audiences why not just leave it as MARS - THE GOD OF WAR which is more cool than SON OF HERCULES VS VENUS.