I am thinking:
Astrology: Fighting the signs of the Zodiac! The giant crab! The Pisces fish things! The ram! This can go through pagan mythology or maybe the chinese zodiac, there's got to be some crazy stuff there. Fighting may or may not take place in space. You get it on with the Pisces twins.
Speaking of space...
1950's era space fiction: Kratos in one of those fish-globe looking space helmets, fighting martians with their ray guns on mars, or climbing up the side of a giant GORT. The last boss is Marvin the Martian, whom you fight on top of the Cydonia face. You get it on with a hot martian lady but it turns out she is Bugs Bunny in drag.