The game was later ported to the NES as Ginga no Sannin in 1987.
Unlike most other role-playing video games of the period, the game takes place in a sci-fi setting instead of a fantasy world; it was one of the first sci-fi RPG's, along with Psychic City and The Screamer. The game was never released outside of Japan.
The game's character designer was manga author Go Nagai, the pioneer of mecha robot design, who also drew the illustrations for the game's package. Much like mecha anime of that era, the game's plot was an epic galaxy-spanning space opera.
The game's background music was composed by Y. Sawamura and Yukihiro Takahashi, a pioneer of electronic music. They included an arranged version of "Rydeen" by Yellow Magic Orchestra (of which Takahashi was a band member, and originally wrote the song for the band) as the battle theme. This was one of the first games to demonstrate the PC-8801's Yamaha FM synthesis sound board.
In the year 2300, the human race created an Earth federation government and spread out into space to begin colonizing the surrounding planets. However, an alien species from the far reaches of outer space began attacking the human forces, putting the very survival of the human race at stake. Though it was only a matter of time before Earth fell to the enormous power of the enemy forces, the Earth's army commander issued an order calling all of the units dispersed around the colonized planets to return to Earth. The player takes the role of a young soldier who was stationed with the Rayieza unit on the planet Mars. The journey begins as he makes his way back to Earth along with the other members of his unit.