Teba's Training Retreat
The quest is unlocked after completing the All Hyrule, United scenario.
"Teba wishes to learn all he can about the gliding techniques of this age. He intends to pass this knowledge on to his son upon his return home. Get him some food so that he doesn't tire out."
"Invigorated by the meal, Teba retreated into the mountains to train. He returned several days later with refined gliding abilities and a new skill to pass on. Even Revali was impressed."