Stoneage, described as a "version of Caveman Ninja," is likely an arcade game sharing gameplay elements or characters with the game Caveman Ninja. Stoneage's gameplay would probably involve platforming, action combat, or puzzle elements depending on how closely it follows Caveman Ninja. Caveman Ninja is known for its side-scrolling action and platforming.  More context is needed to understand the exact differences and the role of the developer.

Stoneage (version of Caveman Ninja)

Steraranger (Moon Cresta version)