"The 15th-night moon," "the full harvest moon," "the mid-autumn moon," and "the potato harvest moon."
Actually, these are all different names for the "full moon."
Since ancient times, Japan has used various names for the moon based on its shape and the season. This game is a Bluff (Doubt) card game that uses those traditional moon names.
You can use your knowledge to play using "correct moon names." You can also mix in "fake moon names" on purpose to play. Who is the best liar?
—description from the publisher (translated)