The dungeon is a vast forest located in the north of the 35th Floor. Like all field dungeons, it is a popular target for players of average level, due to the Clearers almost entirely focusing on clearing the Labyrinth areas of each floor. As the name implies, it is easy to get lost in the forest. In addition to the forest being full of large, towering trees, which divide the forest into areas like a chess board, players within the forest will be transferred to a random area in the forest one minute after setting foot in their current area. Additionally, if Teleportation Crystals are used within the forest, they transport the player to another area in the forest instead of a town. To exit the forest, the player must go through each area in the forest within a minute each. To help navigate through the forest, the player may purchase an expensive map from a shop in the local town. This map checks what areas the player's current area is linked to, allowing them find their way.
On the night between Christmas Eve and Christmas, Kirito comes to the Forest to look for the Christmas event flag boss, «Nicholas The Renegade», near a giant fir tree in a particular corner of the Forest, where he believes that the Boss will appear. Kirito is followed by Klein and the Fuurinkazan, who are followed by members of the Divine Dragon Alliance, into the Forest. While Fuurinkazan hold off the DDA members, Kirito confronts the Boss and is barely able to defeat it off-screen.
One day, Silica was fighting in this field dungeon with a party of six since morning, but, nearing the end of the day, when they were running low on potions and were returning to the city, she got into an argument with Rosalia, a spear user of the party, after which, she decided to leave the party and head out of the forest on her own. Unfortunately, only the leader of the party had the Map, so Silica ended up getting lost in the forest and encountered numerous monsters while wandering the forest, using up both her healing potion and crystal supplies. she eventually encountered 3 Drunken Apes, which killed her familiar, Pina, and would have done the same with Silica, if Kirito hadn't saved her. Eventually, they both use Kirito's Map to safely leave the Forest.