Obtained: Speak with Upa and Bora in the Sacred Land of Korin during the post game as Goku
Objective: Help heal the trees
Travel to the Sacred Land of Korin and head for the base of Korin’s Lookout to find Upa and Bora. Speak with them to learn that the trees are sick, and they are not sure what to do. Agree to help out then make your way to Bulma in Capsule Corp. Speak with her to learn about a medicine that could heal the trees. Following the conversation you will transported back to the Upa and Bora. After filling them in, Goku will head to Baba for a short cutscene. When you gain control of Goku, head northeast towards the sub story marker to find the thieves. Defeat their burglar bots to retrieve the crystal ball, triggering another cutscene. Following the cutscene make your way southeast to Blake Bog. You will find the moss at the base of the giant tree. Collect it trigger a series of cutscenes that will complete the story.