Trojan is an arcade game with regional variations. The "US set 2" label indicates a version of the game released in the United States. This version would likely share core gameplay with other versions, but differences in artwork, sound, or minor gameplay adjustments might exist.  Pinpointing the developer and publisher requires further research. The gameplay would involve likely strategic combat or a scrolling shooter mechanic.  The existence of multiple sets suggests that the game enjoyed sufficient popularity to warrant different releases.

Trojan (US set 2)

Trog (rev LA5 3/29/91)