Only 13,000 of the 30,000 gamers who signed up fulfilled a pledge to spend the weekend playing Half-Life 2 in protest at Valve's lack of communication about Half-Life 3.
Kotaku reports that, while the number of those playing Valve's classic FPS fell far short of what was expected, it still exceeded the game's normal Steam activity by 10,000 players.
"I am personally impressed with what we've achieved today," the protest's organiser said. "We're nowhere near done - in fact, we are currently in the process of planning new activities. This was only our first attempt and, in my eyes, was a success for everyone."
The protest was designed to send Valve a message: "Your oldest and longest-running fanbase would like better communication ... The entire trilogy of episodes was scheduled to be completed and released by 2007, and if Valve has decided to do other things for the time being, that's fine.
"All that we ask for is a basic response on the matter, and to let fans know whether or not the current story arc is scheduled to conclude at another point in time."