Cheat Codes Metaltech: Earthsiege Start or resume a campaign from the main menu. Return to the main menu and select the single mission option. Choose any mission, enter the briefing, and click on the armament option. Select a Herc, return to the briefing, and cancel the single mission. Resume the campaign from the main menu, play the first assigned mission, then save the game. Load the saved game to access all the Hercs, fully armed.