Actually, there are offers in the japanese version (lots of them); although most of them require mobile phones even if they're free. Sadly, I don't think you can do those that need phones unless you live in Japan.
But I don't recommend that page. cuz Artifact is been delate many players almost 1 year ago . She delate my friend's account. she was just join PG with family. but Artifact misunderstood unfair mule players. I don't use that site!=( I think that page is danger for not speak Japanese like a native speaker.