Galaxian

Galaxian is a 1979 arcade shoot-'em-up originally released by Namco. It was not officially released for any Sega consoles (though has appeared as part of Namco Museum for the Sega Dreamcast), but HiCom brought to the Sega Master System in South Korea without a license.

This version is based on the MSX one, handled by Namco themselves, meaning that the Master System version is surprisingly accurate to the arcade original. It does, however, run in the SG-1000 graphics mode, and so doesn't have as wide of a colour palette. It is currently unknown when HiCom ported the game to Sega's console.