I remember the course that was extremely hard.
  • It was the last course in DJMAX.

    Course name is "ShininG Day"

    Course level was "45", and it was higher than Crush!! or Shower day (35)

    And the song is

    Miles (SC) 
    Rolling on the Duck (HD)
    SIN (MX)
    Grid System (HD)
    Cherokee (SC)
    A.I. (MX)
    Chains of Gravity (HD)
    MASAI (MX)
    Jupiter Driving (MX)
    Angelic Tears (HD)
    Super Lovely (MX)

    -1500MAX 6Credits

    Mission : Accuracy 98% or higher, Score 3600000 or higher

    Reward : MAX +1500%, EXP +2000%

    I think ShininG was a pattern designer in DJMAX (There's also a similar course at DMP2 and DMT called "Shinin' finGer", which is also difficult)
  • And then... 2 course is user course

    Night In The Dishallution

    Course Level: 15
    Effect: 5k Random 

    Oblivion(HD Lv.10)
    Space of Soul(HD Lv.12)
    The tokyo(HD Lv.11)
    Midnight Blood(HD Lv.12)
    Seeker(HD Lv.13)

    -500 MAX

    Mission : Accuracy 87% or Higher, Combo 4500 or Higher
    Reward: MAX +350%

    Our Guardians

    Course Level : 7(I Think Lv.14)
    Effect : 5k Random

    Save My Dream(HD Lv.5)
    Ray of illuminati(HD Lv.7)
    Get on top(HD Lv.9)
    NB Ranger(MX Lv.12)

    -350 MAX

    Mission : Accuracy 95% or Higher, Combo 2500 or Higher, Miss 2 or Lower

    Reward : MAX +250%, EXP +250%