i will do it bit by bit, so first the cheats:

Level Select
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To select any level in the game enter this code at the main menu
or during game play:

L1, L2, X, TRIANGLE, L1, L2, X, TRIANGLE.



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Make Hiro Invincible

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This code only works in Single Player mode.

Enter it at the pause menu or during game play:

L1, L2, CIRCLE, SQUARE, L1, L2, CIRCLE, SQUARE.



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One-Hit Kills for Hiro

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This code only works in Single Player mode.

Enter it at the pause menu or during gameplay:

L1, L2, Left Analog UP, Left Analog DOWN, Left Analog LEFT,

Left Analog RIGHT, TRIANGLE, SQUARE, X, CIRCLE.



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Unlock 4 Weapons and Unlimited Explosives

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At either the main menu or the pause screen during gameplay,

enter the following:

R1,L1,R2, L2, circle, x, square, triangle



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Unlock all Magics

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Enter this code in the pause menu or during game play to unlock

all magics:

R1, R2, L1, L2, X, TRIANGLE, CIRCLE, SQUARE.



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Unlock Multiplayer Characters

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Enter this code at the main menu or during game play:

R2, CIRCLE, X, SQUARE, TRIANGLE, RIGHT, DOWN, LEFT,

UP, L2, L1, CIRCLE, SQUARE, L1, L2, L1, CIRCLE, L2, SQUARE.



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Weapons Invulnerable to Wear

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At either the main menu or the pause screen during gameplay,

enter the following:

R1, L1, x, triangle, R2, L2, x, triangle

Some of these cheats might not work but try them out and im sure some will work.

next time i come through to this forum i will be doing the guide to the game.