These vast mazes are found underneath the Swamp biome in the Twilight Forest. There are two levels in each Labyrinth, each with some unique features. The first level is accessible from a small ruin somewhere in the clearing, or you may be able to find natural Caves nearby breaking into it. The second level of the Labyrinth is surrounded by Bedrock and only accessible from an iron-barred room in the first level.
Labyrinths are sumptuously built out of what is called Mazestone, a hard material found in bricks, mosaics, and blue-gray stone blocks. Wooden arches, Torches, and Iron Bars are the most common decorations. The structure is difficult to navigate, consisting of twisty corridors, large rooms, and occasional treasures stashed in the dead ends.
The Monsters that can found throughout the Labyrinth include Fire Beetles, Slime Beetles, Pinch Beetles, Maze Slimes, Cave Spiders, Creepers, Endermen, and Minotaurs. Maze Slimes and Minotaurs are unique to the Labyrinth. The Labyrinth includes some light sources, but adventures are advised to bring plenty of torches to light the maze and cut down on monster spawns.
There are many treasure chests in the Labyrinth, with several categories of treasure. Dead end treasure rooms are protected by Iron Bars and may be trapped. These chests include Maze Wafers, Blaze Rods, Ironwood Ingots, and occasionally Golden Apples and Steeleaf.
On each level of the Labyrinth, one can find up to two Minotaur Hideouts each containing a Minotaur Spawner and Treasures. These treasures can include Iron Ingots, Steeleaf, Potions, and Ironwood Ingots, as well as full Ironwood and Steeleaf armor pieces. These chests can also contain the essential maze map focus, which can be used to create a Maze map.
Deep down on the second level, one can find a Minoshroom's prison. The Minoshroom is a strange creature that is locked away in a its prison. It can be found holding a Minotaur Axe and guarding valuable treasure, similar to the treasures that can be found in a Minotaur Hideout. Smart adventurers advise to be very cautions around this creature.
Finally, it is rumored that there is a third category for all the best treasures. These treasures are said to lie within a secret vault that you will almost certainly need a Maze map to find. The second level of a Labyrinth will contain a secret room that contains very valuable treasures such as the unique Mazebreaker, Emerald Blocks and Emeralds, some Steeleaf, some Ironwood, and occasionally an Ender Chest to stash these treasures in safely. You can also find highly enchanted armor, tools, and weapons within these treasures. Vault rooms are hidden by several layers of Mazestone and will have four large chests in the center. The four large chests will be heavily guarded by 16 wooden pressure plates which are resting on TNT. Sand will be resting on Mazestone that is above the wooden pressure plates, preventing easy entrance from the top. Entrance from the bottom is also difficult due to the bedrock floor. Great care should be taken when entering the secret room so as to not blow up the valuable loot.
When using the progression system, the Labyrinth will be surrounded by a glowing green field. Blocks and monsters inside the tower proper will be protected. Additionally, the whole swamp will be covered in a haze of mosquitoes. Killing the Lich and picking up one of the magical scepters he drops will dispel the protection.