Released in May 1995 in the USA.
Released outside US as "Viper Phase 1
". The known differences between the versions are:
Secondary Weapons Systems: The original version of Viper Phase 1 has an exhaustible secondary weapon system. The amount of ammunition remaining in a secondary weapon is indicated by a meter on the screen. All secondary weapons in the original version are fully powered up, and are more devastating than in the USA version, which gives the secondary weapons levels of power in lieu of unlimited ammunition and reduced firepower.
Bomb Deploy Times: The USA version speeds up the deploy time of the Bomb, of which becomes the standard for when the ship appears in the Raiden Fighters series.
Medals: In the USA Version, medals stop shimmering for a brief moment, during which their point values are higher than usual. This feature was also present in Raiden DX. Additionally, the egg-shaped medal carrier pods appear much more frequently in the USA Version.