Note: For games that were downloaded from Steam, to use cheats in Single Player mode, start the game with the ' -applaunch -dev -tconsole' command line parameter. Also, any code can be used as a command line parameter by prefixing it with the '-' character. Then, enter one of the following codes to activate the corresponding cheat function. When you use the Multi tool, all three main camera controls are available. Type ' sv_cheats 1' and press to enable cheat mode. VERC: XSI EXP for Half-Life 2 Tutorial - Camera Control Last edited 2 years. While playing the game, press ~ to display the console window. Double click 'Half-Life 2: Episode One' to start the game. Click the 'Launch Options' button, then type ' -console'. Right click on it and select 'Properties'. Open Steam, go to your 'Play Games' menu, and select Half-Life 2: Episode One. Then, start a new game and choose a level to get an option to play it with an audio commentary track.