Mal:Valve navigasjon

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GoldSrc	Half-Life Half-Life: Opposing Force Half-Life: Blue Shift Half-Life: Decay Counter-Strike Counter-Strike: Condition Zero Day of Defeat Team Fortress Classic
Source	Half-Life 2 Half-Life 2: Lost Coast Half-Life 2: Episode One Half-Life 2: Episode Two Counter-Strike: Source Day of Defeat: Source Team Fortress 2 Left 4 Dead Left 4 Dead 2 Portal Portal 2 Alien Swarm
Nøkkelpersoner	Gabe Newell Mike Harrington