Half-Life Codes

Invincibility
Go to the Cheat Code screen in the Options menu and enter the following cheat to unlock Invincibility: LEFT, SQUARE, UP, TRIANGLE, RIGHT, CIRCLE, DOWN, X. Press START to confirm code. If done correctly, the code will appear in the box to the right.

Unlimited Ammo
Go to the Cheat Code screen in the Options menu and enter the following cheat to unlock Unlimited Ammunition: DOWN, X, LEFT, CIRCLE, DOWN, X, LEFT, CIRCLE. Press START to confirm code. If done correctly, the code will appear in the box to the right.

Unlock Alien Mode
Go to the Cheat Code screen in the Options menu and enter the following cheat to unlock Alien Mode: UP, TRIANGLE, UP, TRIANGLE, UP, TRIANGLE, UP, TRIANGLE. Press START to confirm code. If done correctly, the code will appear in the box to the right.

Unlock Invisibility
Go to the Cheat Code screen in the Options menu and enter the following cheat to unlock Invisibility: LEFT, SQUARE, RIGHT, CIRCLE, LEFT, SQUARE, RIGHT, CIRCLE. Press START to confirm code. If done correctly, the code will appear in the box to the right.

Unlock Slow Motion Mode
Go to the Cheat Code screen in the Options menu and enter the following cheat to unlock Slow Motion Mode: RIGHT, SQUARE, UP, TRIANGLE, RIGHT, SQUARE, UP, TRIANGLE. Press START to confirm code. If done correctly, the code will appear in the box to the right.

Unlock Xen Gravity
Go to the Cheat Code screen in the Options menu and enter the following cheat to unlock Xen Gravity: UP, TRIANGLE, DOWN, X, UP, TRIANGLE, DOWN, X. Press START to confirm code. If done correctly, the code will appear in the box to the right.

Uplink Mod!!!!!
For this code to work, you will need a copy of "Official U.S. PlayStation Magazine" Issue 57 (The one with Jango Fett on the cover) and its demo disc. From the Half-Life main menu go to option and the the cheats menu. Enter the following cheat: Triangle, Square, Left, Right, Circle, X, Up, Down. It should open an extras menu on the options screen. Go to the extras menu and it should say opening disc tray. When it opens remove the Half-Life disc and put in the issue 57 disc and it should load the Half-Life Uplink Mod. Enjoy!

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