Moshi Monsters is a British children's web browser massively multiplayer online role-playing game (MMORPG) aimed at children aged 6–12. At its peak, it had over 80 million registered users in 150 territories worldwide. Users could choose from one of six virtual pet monsters they could create, name and nurture. Once their pet had been customized, players could navigate their way around Monstro City, take daily puzzle challenges to earn 'Rox', play games, personalize their room and communicate with other users in a safe environment.