Ultimate Gifts are the final reward(s) you can obtain from each Season, and you must have the Season Pass to unlock them.
You will need to trade Seasonal Hearts with the Season’s Quest Giver to unlock each Ultimate Gift. To obtain Seasonal Hearts you will need to spend Seasonal Candles to unlock them from the top of each Seasonal Spirit's friendship tree.
Harmony Hall, located in the Village of Dreams in Valley of Triumph, will offer a few instruments inspired by existing instruments in Sky as IAP. These will be permanently available in Harmony Hall; they are not time-limited to a particular event.
You will need to trade Seasonal Hearts with the Season’s Quest Giver to unlock each Ultimate Gift. To obtain Seasonal Hearts you will need to spend Seasonal Candles to unlock them from the top of each Seasonal Spirit's friendship tree.
Harmony Hall, located in the Village of Dreams in Valley of Triumph, will offer a few instruments inspired by existing instruments in Sky as IAP. These will be permanently available in Harmony Hall; they are not time-limited to a particular event.