Nearly a year since it announced the port, Treasure has revealed that its cult favorite shoot'em up Radiant Silvergun will release for Xbox Live Arcade on September 14, accurate arcade/Sega Saturn transparencies and all.

This downloadable of the previously Japan-only game will add online co-op and a new Ikaruga-style gameplay mode. It aso has a pretty neat avatar award that you can unlock after playing Story mode 20 times!

[Via N2O1990]