Prehistory: Punching primitives.
Prehistory: Tackling traps.
Prehistory: Bullying bears.
Roman Empire: No, he's not exactly a gentleman.
Roman Empire: Grappling with gauls.
Japanese Middle Ages: Slapping samurais.
Japanese Middle Ages: Striking sumos.
European Middle Ages: Kicking knights.
European Middle Ages: Jabbing jailors.
Conquistadorrs: Duelling dames.
Conquistadors: Intimidating incas.
Wild West: Gunning down gangsters.
Wild West: Thumping tramps.
Modern Wars: Shooting soldiers.
Modern Wars: Roughing up rebels.
Modern Wars: Maiming marines (nice pin-up, though).
Future: Annoying androids.
All levels: Warding off virus.
Special stage: Destroying doppelgangers.