Dota 2 may not be nearly as popular as its rival, League of Legends, but to be fair, no game is. That shouldn’t take away from the fact that Dota 2 is still insanely popular. In fact, the game is so popular that it has become the first game in Steam’s history to have more than one million people playing the game at the same time. Counter-Strike: Global Offensive comes in at number two with 420,000 concurrent users.