Star Soldier:Vanishing Earth
2nd Bonus Level
This Path is in Mission 3. When you come to an area with 7 ships -- 6 green and one red -- shoot the red ship. Do not shoot any of the green ships or the code will not work.
Credit Goes To: Jeremy Turner via IGN 64
 2nd Bonus Level
 3rd Bonus Level
 1st Bonus Level
 Gallery & Level
 Select
3rd Bonus Level
A bit into level 4 you will see a group of enemies, 4 green and 4 red. The green enemies will appear first, and the red will follow behind. Wait until the red ones pass over the "pyramid"-looking blocks, just before they leave off of the top of the screen. Destroy the red ships at this point (the special multi-attack seems to work well). This will open the path to the third secret level (a cool retro level--you should recognize it if you played the original).

1st Bonus Level
To get the first bonus level find the area which has 5 small "towers" -- 4 blue surrounding a central red one -- just before the level takes a 90-degree turn upward. First shoot the 4 blue ones, then the red one last. The secret path will open up, you will have a different path, you will skip that level's boss, and you will then play the 1st bonus level which has a different boss. You also get a 10,000,000 point bonus for getting the different path.

Gallery and Level Select
Beat the game to gain access to a 3D enemy gallery where you can view and rotate the enemy models. You also gain access to a level selection option where you can choose which level to start from.
Credit Goes To: Ey Wuz Hear via IGN 64