Condition: You must complete the quest of Goddess Erina
Process: 1. Take the Sky Jade with you and go to Lion Isle to touch Saint Lion
2. A hidden door will be opened.
3. Head to Valkyrie and have a talk with him to enter combat.
4. Your opponents will be 2 Level 125 water New Trainees with 27500 HP and specializing in W.T. Beating, Freezing Spell, Recovery, 2 Level 130 fire New Trainees with 27000 HP and mastery of the Fire Stone Bead, Hagendis Beating and Mess Spell, 2 Level 125 wind New Trainees with 26890 HP and mastery of Afterimage Beating and Coma Spell, and 2 Level 130 earth New Trainees with 28000 HP and mastery of Aerolite Beating and Terrafication.
5. You need to pay 7 stars after completing the quest
Rewards: Fire: Zavrl's Wing (all attacks made with 105 SP and one Fire Glaze cost)
Water: Najas's Memory (help teammates restore HP with 127 SP and one Water Glaze cost)
Earth: Gaea's Guard (increases the defense of your teammates with 120 SP and one Earth Glaze cost)
Wind: Gephil's Mutter (grants an increase to your teammates' speed with a certain amount of SP and one Wind Glaze cost)
As these skills are activated each time, Glaze will be worked out and these skills will be disabled..
PS: You can re-learn these skills with 7 stars.