Note: Requires White Boa.

Break the ice in the NW part of the continent until you get the prompt to land to the "Snowfields of the Northern Land"

Jansen will remind you that a legendary spell can be found in this area. Also, youll notice that your partys HP is slowly being drained. This is some sort of a little maze. Just head to the direction where the wind/particles are coming from. Do this for at least 5 times and youll encounter an optional boss battle.

Boss Battle:
Equip some good rings with Bio-Killer skills. This boss absorbs elemental damage so it will be a good idea cast healing and support spells instead. It takes turn twice (probably because of doublecast) Its attack patterns seems to be fixed; Prisma and Death/ Leveler/ All-Curse and Forceus. Leveler deals considerable damage but fortunately, it can only target one character. With only HP9350, this batlle shouldnt take that long. Just make sure you equip Anti-Curse for your characters and avoid healing the boss with elemental attacks. Gamble works fine, but I suggest leaving the offensive to your frontline. Buff them with Powerus with Bio Killer Skills and this boss is a goner.

Aside from the Blue Dragons Eye accessory that youll get as battle spoils, youll also get LV8 Black Magic: Leveler. The corresponding achievement for this battle will be unlocked as well.