Luna has visited the Ancient Forest on her journeys to the Spirit's world. When she entered the Spirit World for the first time, at the age of 3, she met Ancient Fairy Dragon, Kuribon and other spirits. Ancient Fairy Dragon told Luna of evil and threatened the land and asked her to promise to protect it. Unable to bear the responsibility, Luna managed to leave the Spirit World.
At the age of eleven, Luna returned to the Spirit's World again in the Ancient Forest, while she was Dueling Professor Frank at the Fortune Cup. Subconsciously Luna continued to Duel in the human world, while her conscious self lived the events of the Duel in the forest. Her own monsters assisted her as she battled "Ido" and Frank, who continued to pollute the forest. As Ancient Fairy Dragon proceeded to devour Frank, Luna forced the Duel into a DRAW to save Frank. This returned her and Frank to the human world.