The free-to-play online children's game Moshi Monsters from UK-based developer Mind Candy has notched up more than ten million registered players.
According to the company's figures, more than one million new users are joining every month and the site has become one of the fastest growing children's sites in the world.
The social online game Moshi Monsters allows children to raise a virtual monster while solving educational puzzles that test their maths, spatial awareness, logic and vocabulary skills. Successfully completing puzzles rewards users with a virtual currency that can then be spent on customising their in-game home.
"We've been astounded with the growth of the game this year," said Mind Candy CEO Michael Acton Smith. "Most of the growth has been due to word-of-mouth which is a great endorsement from our players that they love the Moshi world and want to share it with friends."
Mind Candy is a London-based company, set up in 2004 by Smith, who previously founded Firebox.com and the event Second Chance Tuesday.