Mega Man X8 cheats and cheat codes for Playstation 2

Go to the title screen. When the "Press Start" message appears, enter 
any of the following button combination cheats:

Unlock Sigma-Blade:
Press L3, L3, R3, L3, L3, R3, L3, L3, R3, L3, L3, R3. 
Begin a new game and purchase at the development shop.

Unlock Alia
Press Down, R1, Up, L1, Square, X, Triangle, Circle.
Begin a new game and purchase at the development shop.

Unlock Black Zero
Press L1, L1, R1, R1, L1, L1, L1, L1. 
Begin a new game and purchase at the development shop.

Unlock Layer
Press Square, Square, Right, X, R1.
Begin a new game and purchase at the development shop.

Unlock Palette
Press R1, X, Left, Square, Square.
Begin a new game and purchase at the development shop.

Unlock Ultimate Armor X
Press Left, Left, Left, Right, Right, Right, Left, Left, Left, Left, 
Right, Right, Right, Right.
Begin a new game and purchase at the development shop.

Unlock White Axl
Press L2, L2, L2, R2, R2, R2, L2, L2, L2, R2.
Begin a new game and purchase at the development shop.

Fight against Cut Man at the end of Optic Sunflower's level:
Press Left, Circle, Up, Triangle, Down, X, Right, Square, L1, R1, L2, R2. 

Unlock Axl's White Armor
Collect all of Axl's metals and use Axl to beat the last Boss with a 2x 
attack, then finish the game.

Unlock X's Ultimate Armor
Collect all 8 armor pieces and all of X's metals, then finish the game

Unlock Zero's Black Armor
Finish the game with all of Zero's metals

Unlock Zero's Sigma-Blade
Finish the game and load back your cleared saved game file. 
You can purchase Zero's Sigma-Blade at the R&D Lab.

Different ending:
Kill Lumine with different charachters (Axl, X, or Zero) to watch the 
alternate ending.

Unlock Infinite money
Spend all of your money by purchasing any items in the R&D lab.
Make sure your money is at 0, otherwise this trick will not work.
After, check anything you have not bought, and you should be able to buy it. 

Getting money easily
Stay in one area and run right and left direction. You will receive the money 
when you run left, and you must run right or it will not work. Do not push
Circle going both ways.

Unlock bonus characters
Finish the game and load back your cleared saved game file.