Star Soldier: Vanishing Earth Codes -

Bonus options:
Complete the game under the "Regular" difficulty setting to access level select and enemy ship preview options.

Alternate mode selection screen:
Complete the game under the "Beginner" difficulty setting to change the background on the mode selection screen.

Start with best weapon:
Hold after selecting a craft in normal mode. When you start shooting, you will have the most powerful weapon that craft has available.

Avoid damage:
Roll if your ship is about to be hit by a missile. If done correctly, the missile will bounce off your ship.