During the final part of the game, once you unlocked the flying upgrade, you will be told of some trials you can do to help prepare for the final battle. This is located through one of the doors in the underground part west of the Warrior’s Rest Inn. You will have to go through an area before reaching Trial Isle. Once you reach that location, check the north end of the outside portion of Trial Isle to find the Tockle.
Upon arriving in the area, you will be in a throne room and the king will be unable to speak. There are two chests right in front of them, containing a Seed of Life and 120G, which you can freely open. So, talk with Gwaelin to learn that some fiend named the End of Time put a curse on her father, rendering him unable to speak. She had heard about something called spectrum nectar that can cure him, but only those who “have brought peace to the world” can lay their hands on it, giving you the quest, Curse Got Your Tongue?.
With that little bit of knowledge, you cannot complete this area until you finish the final part of the game (Act 3). That means this could possibly be the final Tickington area you complete, since the others can be done without needing to complete the final part. Once you do, you can create a save after the credits and load up that save to go back to the main game before beating that boss. Travel to Tickington and as you move, the Tockle by the entrance will stop you and hand over the Spectrum Nectar. Turn this over to Gwaelin to finish the quest, with your reward being a Pallium Regale.