Research has shown that massively multiplayer online role-playing games (MMORPGs) have the potential to offer language learning opportunities. However, there is a dearth of research exploring student attitudes about the potential of these games for language learning. We used the language learning principles framework proposed by Brown and Lee (2015) to explore the attitudes of informal Iranian EFL gamers about the potential of the MMORPG environment for language learning. Using a mixed-methods approach, data collected by means of a questionnaire (N = 500) and semi-structured interviews (N = 20) showed that participant attitudes aligned with eight language learning principles (i.e. autonomy, transfer, reward, self-regulation, identity and investment, interaction, languaculture, and agency). The findings of the study highlight the potential of the MMORPG environment for language learning. Parents and EFL teachers should consider the potential affordances of the MMORPG environment as an alternative or complement to formal English language learning environments.