In game tutorials are always best, but I guess for a 48 hour game jam some people just don't have enough time to put it in the game itself.
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We didn't have time to make the tutorial, we surely will after the jam ratings finish ^^ About the input, there is no need to synchronize them exactly. If you are pressing the correct button when the mark hits the green area, you're good. Glad you played it and liked the art :D Thanks for the feedback