CheatCodes.com has all the official Space Invaders PSX cheats to unlock everything. If you know of any that we don't have, please let us know.
All published and official codes as of Monday May 20, 2013 for Space Invaders are shown below. We also have this game on PlayStation, Nintendo64, Game Boy, and sometimes tricks from other game systems will also work on PlayStation.
At the main menu, select either one or two players and press Circle (instead of X) to begin the game. Then a selection screen that allows any level, including planet Mercury with a new power-up and an "Alien World" featuring the best background in the game will appear.
Pause the game and press Down, Left, Circle, Down, Right(3).
Enable the "Level select" code, choose level 00, and complete it to unlock an ending, classic mode, and credits. Press Right when selecting then number of players to access classic mode. Enter the options screen to access the credits.
Pause the game and press Right(3), Down, Circle, Left, Down.
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