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The following games all support bot additions via console commands: Counter-Strike: Global Offensive Counter-Strike: Source Counter-Strike 1.6 This process will vary slightly depending on your selected game: Counter-Strike: Global Offensive Click OPTIONS at the top of the home page, click GAME SETTINGS in the drop-down menu, and switch the "Enable Developer Console" option to "Yes". Counter-Strike: Source and Counter-Strike 1.6 Click Options, click the Keyboard tab, click Advanced..., and check the "Enable developer console" box. Either create a new online game, or open your server and connect to it before proceeding. Doing so will bring up the developer window on the right side of the Counter-Strike screen. The ~ (tilde) key is typically found below the Esc key in the top-left corner of the keyboard. Type in bot_add_ct and press Enter to add a bot to the "Counter-Terrorists" team, or type in bot_add_t and press Enter to add a bot to the "Terrorists" team. Open the console by pressing ~, then enter in bot_difficulty 1 for easy bots, bot_difficulty 2 for medium bots, or bot_difficulty 3 for expert bots.
Open a Counter-Strike game. Enable the developer console. Start a game. Press the ~ key. Add a bot. Change a bot's difficulty.