Halo Developer Console + Commands

rasterizer_stats <#> = 2 displays a frame rate counter along with categorized vertex and triangle counts for the scene being viewed. 4 displays information on memory usage for the game. 5 displays a simple frame rate counter and information such as maximum, minimum and average frame rates for the scene.
cheat_omnipotent <#> = Enabling this cheat makes the player's shots kill anything they hit—instantly (and if the player shoots an indestructible vehicle, like a warthog, it will render it useless as the player cannot enter it).
cheat_all_powerups = Spawns all powerups near the player.
cheat_all_vehicles = Spawns all standard vehicles near the player.
cheat_all_weapons = Spawns all weapons near the player.
cheat_bottomless_clip <#> = Enables a bottomless clip—the player never has to reload, and weapons never overheat.
cheat_bump_possession <#> = Allows the player to control any character by bumping into them.
cheat_deathless_player <#> = Makes the player invulnerable to any damage, including the maximum falling damage height restrictions.
cheat_infinite_ammo <#> = Gives the player unlimited ammunition.
cheat_jetpack <#> = Prevents falling damage from occurring—useful for moving lower in a level or with cheat_super_jump.
cheat_medusa <#> = When this command is enabled, any enemy unit that sees the player will be instantly killed.
cheat_spawn_warthog = Spawns a standard Warthog near the player.
cheat_super_jump <#> = Allows the player to jump very high, which is useful for maneuvering around a level during its construction.
cheat_teleport_to_camera = Teleports the player to the current camera position.
debug_objects <#> = Shows visual representations of the game objects' or models' bounding radii and collision models.
debug_portals <#> = Draws or outlines the portal definitions in the game.
debug_sound <#> = Shows visual representations of the sounds being played and their audible radii, along with labels indicating the specific sound being played.
error_suppress_all <#> = Enabled by default; this cheat suppresses all error messages. Disabling it will show errors that occur during gameplay, something that is useful when debugging content and game problems.
game_speed <#>1-20 = Changes the speed of the game. It is useful for pausing the game or for traveling around a environment quickly during level creation or debugging.
map_name [map name] = Manually loads a specific level.
debug_camera_save = Saves the current player camera as the debug camera.
debug_camera_load = Loads the most recently saved camera location; if there is no saved camera, it loads the camera at numerous default positions.
camera_control <#> = Loads the default camera in the player's biped.