You first need to finish the singleplayer campaign and then you are allowed to play the multiplayer campaign and after you finish them both you are allowed to play everything. Counter-Strike: Source > General Discussions > Topic Details. Date Posted: Jul 19, @ am. Nov 01, · Online multiplayer game. Based on the extremely popular mode to Half-Life, Counter-Strike, this game is a completely redesigned version of it on a new engine. The combination of realistic and fast arcade shooter pace – one of the key elements that made the game so popular. The counter-terrorists (special forces) fighting against terrorists. Hi! We present to you our map “de_militarybase_gigifty” (bomb/defuse mission) for "Counter-Strike: Source". This map was made from scratch and represent a block-warhouse of a former Soviet military base with weapons, ammunition and IFV (infantry fighting vehicles).