Codes-
Full Health and Ammo During Gameplay
Press pause during battle, (shoulder buttons) press:
L1, L1, L2, L2, L1, R1, L1, R1, R2, R1
(Your level will go down once each time you do this.)
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Unlockables-
Two secret characters in Versus mode.
To get the two hidden characters in versus mode, simply beat the game again on any difficulty level. Once you do it, go to versus mode and you will find the two new characters playable.
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Unlock 2 secret levels in Versus Mode-
To open up two hidden levels in versus mode, simply beat the game again on any difficulty level. Once you beat the game again, go into versus mode and you will have the two new levels.
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Unlock Versus Mode the Easy Way-
At the title screen that says Press Start Button, press Circle, X, Right, Left, Right, Left, Down, Down, Up, and Up. Now, Versus mode is accessible with all Frames and stages.
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Secrets-
How To Get the Second "True" Ending
Destroy ALL buildings and survivors during missions and SOS missions. Also, you must destroy the colony shaft completely during the fifth and final SOS mission in the game. Afterwards continue onward as normal. Tyrant will be your final boss. After defeating Tyrant, go to the MOUNTAIN.1 stage and you'll recieve the bad ending.
Note: This can be done on any difficulty level.
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Different Ending Music-
Play the game on any difficulty setting and get an A rank in all 5 rescue missions. During the credits, you'll hear other music than you normally would.
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Final Comment-
Depending on your final rank, you will get comment from one of the main character. Get the B rank to hear Leo. Get the A rank to hear ADA and get the S rank to hear Celvice.