Half-Life Passwords and Secrets (PS2)

Half-Life, a first-person shooter, requires the player to perform two kinds of tasks: combat and puzzle solving. Unlike its peers at the time, Half-Life utilized scripted sequences, which range from small events, such as an alien ramming down a door, to major plot points. While most contemporary first-person shooters relied on cut scene intermissions to detail their plotlines, Half-Life's story is put forth entirely through scripted sequences, keeping the player in the game at all times. In line with this, the player rarely loses the ability to control Gordon, who never speaks and is never actually seen in the game.

Half-Life has no "levels", opting instead for a continuous world divided by short load times to minimize interruptions in gameplay. That said, the game can clearly be split up into distinct "chapters", the titles of which will flash up on the screen at the start of each one. The game regularly integrates puzzles, such as navigating a maze of conveyor belts. Some puzzles involve using the environment to kill an enemy.

Codes

Cheats

Up, Triangle, Up, Triangle, Up, Triangle, Up and Triangle - Alien Mode

Triangle, Square, Left, Right, Circle, X, Up, Down - Bonus levels

Down, X, Left, O, Down, X, Left, O - Infinite Ammo

Left, Square, Up, Triangle, Right, Circle, Down, X - Invincibility

Left, Square, Right, Circle, Left, Square, Right, Circle - Invisibility

Right, Square, Up, Triangle, Right, Square, Up, Triangle - Slow motion

Up, Triangle, Down, X, Up, Triangle, Down, X - Xen gravity

Passwords

Unlock all Decay missions
Go to the Options, then Cheats. To enter the code you must have two controllers.

p2_R3, p1_L3, p1_up, p1_up, p2_down, p2_down, p1_left, p1_right, p2_left, p2_right, p1_X, p1_O, START - All Decay missions unlocked including bonus mission Xen Attacks

Unlockables

Bonus Alien Mission
Get an A-grade on all 9 of the Decay missions. If you successfully do this, you'll get to play a 10th level as a Vortigaunt alien. Getting an A-grade on this level will formally unlock the Alien Mode. (Note: the best way to ensure an A-grade for a level is to get at least 25 kills.)

Secrets

Uplink Mod
For this code to work, you will need a copy of 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 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 ask 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!

Here's some gameplay footage from the PS2 version of the best shooter ever created: