The Kyouen Add-on for Groove Coaster has 6 achievements.
Play Kyouen 20 times
Play Kyouen and clear all of SIMPLE, NORMAL and HARD
Play Kyouen and get A Rank in SIMPLE, NORMAL and HARD
Play Kyouen and get S Rank in SIMPLE, NORMAL and HARD
Play Kyouen and get S+ Rank in SIMPLE, NORMAL and HARD
Play Kyouen and get S++ Rank in SIMPLE, NORMAL and HARD