User Summary: Erinthor Mountain Terrain Tray - Multi-pack is part of the Wildlands wilderness terrain series. Terrain trays are made of thin ferrous metal sheet so the magnetic pieces can stick to it. Different terrain artwork printed on the surface of each side. They come in gridded and gridless versions. This item was initially available as an add-on during the Wildlands Kickstarter. Erinthor Mountain Terrain Tray - Multi-pack comes with these 2 pieces. (2) Mountain Ground / Packed Earth 12x12 (2) Mountain Ground / Packed Earth 6x6