Fireflies

From BoardGameGeek:

At the heart of the Vastwood stands a gigantic tree, whose immense branches stretch far up into the heavens. It is called the Heart Tree, and it holds within it the Crystal, source of all life. Nori and Tan are Sylvans, a people who live inside the Heart Tree. As secret guardians, they watch over the Tree and the Crystal. To light the countless tunnels that wind through the trunk, the Sylvans have tamed fireflies, whose natural glow lights their way. The inhabitants of the Vatswood call them "the firefly tamers." Fireflies is a cooperative game for two players that invites you to embark on a fantastic adventure: the epic journey of Nori and Tan to save the Vastwood from the Darkness. Guiding your partner across otherworldly and perilous landscapes, you'll explore hostile lands, meet a full cast of characters, and complete grand quests. The Fireflies story consists of 8 Chapters, each representing a game, with its own objective and additional rules. On your turn, explore your surroundings by playing a Firefly token from the shared reserve on your board: your interactive booklet visually and textually recounts your character's adventures. Your choices will change the course of events, and you must use each uncovered item and secret wisely. Two heroes with two intertwined storylines... but only together, by sharing discoveries and ideas, will you unravel the mysteries of this epic odyssey... -description form the publisher