This was licensed much later than "regular" Fluxx (3.0), and some different decisions were made. Our art was already in color, and really great, so they just used ours and did not make their own. They also used our exact card back (Japanese Fluxx had a slightly different card back) and the cards are what we'd consider regular weight.
For the record, unlike Japanese Fluxx 3.0, no English is included on the cards at all, so you really might go insane trying to figure out how to play if you don't read Japanese. Licensed by Hobby Japan.
PS: Given that the card back has the exact same art as ours (which is almost unheard of for an internationally licensed version), we hoped that perhaps our own promo cards could be mixed with this deck. It turns out the cards are the exact same size as well, but the corner radius is just a little off. You could still choose to try some of our promos in the deck, if you wanted to. If the draw pile was sufficiently untidy, one might not notice.
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