In standard platforming stages switches weapons, fires and jumps. is disabled in flight stages and fires rockets to the ground. Controls can be configured in the options menu.
It's noteable that ammo is limited in this game, also that having physical contact with enemies doesn't always mean the player will take damage. Extra weapons can be collected, without replacing the previously owned weapon. Once all ammunition has been spent, Robocop punches. Some boss fights also limit the player to punches.
Difficulty levels modify enemy and item placement. Most stages feature invisible checkpoints and end with a boss fight.
Differences between the SNES and MD version.
The Sega Mega Drive version runs at a higher resolution, with more horizontal screen space
The Sega Mega Drive version has more options, such as difficulty level, lives and continue modification. Default settings are more difficult (1 life vs 3 lives).
Flight stages are very different. The MD version has nighttime stages, the SNES version has daytme stages that also feature a scaling effect. Enemy layout aside from bosses is very different.
Extra voice sample "Thank you for your cooperation" and intro scenery in the Sega Mega Drive version, ending shows a city scenery instead of Robocop from the score screen
Misc. color count and sound differences, with the Sega Mega Drive having less bright colors.