The following cheats are available for Halo on the PC. No matter what you do, you will not be able to activate cheats in on-line games.

In order to use cheats for Halo, you will need to begin the game with the following command line parameter:

-console -devmode

More information on beginning a game using command line parameters can be found here.

Here are the cheats that are available for Halo (custom edition) on the PC.

Toggle Instant Deaths For Enemies That See Player
Cheat code: cheat_medusa <0 or 1>

Set Game Speed
Cheat code: game_speed <0-20>

Clear Console Window
Cheat code: cls

Toggle Unlimited Ammunition And No Overheating For Human Weapons And Plasma Weapons
Cheat code: cheat_bottomless_clip <0 or 1>

Unlimited Ammunition
Cheat code: cheat_infinite_ammo <0 or 1>

Super Jumps
Cheat code: cheat_super_jump <0 or 1>

Possess Touched Character
Cheat code: cheat_bump_possession <0 or 1>

Invincibility
Cheat code: cheat_deathless_player <0 or 1>

Spawn Warthog
Cheat code: cheat_spawn_warthog

Spawn All Power-Ups
Cheat code: cheat_all_powerups

Spawn All Vehicles
Cheat code: cheat_all_vehicles

Spawn All Weapons
Cheat code: cheat_all_weapons

Teleport Player To Current Camera Position
Cheat code: cheat_teleport_to_camera

Save Current Camera Location
Cheat code: debug_camera_save

Go To Saved Camera Location, Away From Player
Cheat code: debug_camera_load

List Player Names And Numbers On Server
Cheat code: sv_players

Ban Indicated Player From Server
Cheat code: sv_ban <player name or number>

Kick Indicated Player From Server
Cheat code: sv_kick <player name or number>

Send Message As **SERVER** User Name
Cheat code: sv_say <message>
Note: When sending messages use the ( _ ) underscore symbol in place of spaces in your message.

Quit Game
Cheat code: quit