Can't imagine using MTG to learn a language. But it does seem intuitive in hindsight. Back when I played in the junior super series and nationals I could recall almost every card and what it did. So I can see how that leap would be tantermount. Kudos.

> Can't imagine using MTG to learn a language.

Note that he's starting from N2 Japanese, which is already a high level of Japanese proficiency (although it does not test writing/speaking at all, so it's very feasible to have N2 yet be terrible at conversation). He's not exactly learning hiragana from M:TG.

The M:TG competitions are giving him a framework to practice that conversation, which believe it or not can be hard to come by in Tokyo without deliberate effort (see 'expat bubble'). The vocab/grammar on the cards is mostly incidental to all that. If he was playing online M:TG in Japanese he wouldn't be getting anywhere near the payoff.

tantamount