The mushroom kingdom was a huge, mushroom-block rectangular town in a swamp built by Fzone1000 in the Roundcastle era. It was one of the most popular features of the server, frequently visited by Fzone10000, nacnudd, 17454538, weltinator2, peanutandlime, and allieandfluff. The kingdom featured glowstone lighting, diamond, gold, and mycelium flooring, a large, multi-storied, biome-themed house by Fzone1000 and a complex sewer system that connected to a mine and was very dark, causing many mobs to spawn, as well as using various spawners. Fzone1000 and originally nacnudd lived here, and Weltinator2 lived directly outside. 

The kingdom is planned to be revamped in the Steamothic map.