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From the campaign:
Iron Ring Games, a Canadian game and game component company, is proud to introduce Labyrinths, customized modular terrain. Labyrinths is our new 25mm gaming terrain that is a fresh approach to the classic 3-D terrain used with RPG's, board games, and tabletop war games.
Labyrinths are made from a grey color-infused, high strength die stone, making the game pieces durable, affordable, and visually appealing right out of the box.