Yes, you read that title right. Riot Games' free-to-play MOBA title League of Legends has revealed (via Wall Street Journal) that their active user playerbase now has more than 27 million active user accounts, essentially doubling the 12 million report back in December of 2012. The company also said it has counted peaks of over 7.5 million customers playing the game at the same time each day, up 50% from the 5 million the company counted in March of last year.

Partially contributing to that success is the game’s business model, which allows players to either go free-to-play completely, or purchase individual characters at their pleasure. According to last week's report, that choice of purchase has made the company more than $600 million in revenue for the year. Though it may not have been the highest grossing title of 2013, with that win going to CrossFire, it is still a sizeable amount of cash to be gaining from what is essentially a free-to-play title.

One thing to take away from this is that League of Legends is just one of the golden examples of free-to-play working as intended, enabling players the choice of unlocking the items in-game or with micro-transactions. Those that do go the pay route aren't gaining any out-of-reach benefits, besides that of getting the champion earlier than usual. Almost all of the game's store upgrades can be bought in-game, and those that can't are simply your standard flair items that add no game benefit. What Riot has done is essentially found the perfect balance, and it looks like they aren't going anywhere in the near future.