Made famous by the decisive battle waged upon it during the War of Humanity, the nearby plane of Nishnatoba has been popularised in modern times by combatants and warriors alike, as it is one and the same with the interior battleground of the Matsuhama Arena. In every known area of Nishnatoba, you may be killed at any time, for any reason (or no reason at all), and without retribution.
When a House receives an icon, that icon is placed on Nishnatoba. Each icon has a specific area of the plane set aside for itself, and all such areas are restricted to ten rooms or less. These areas may be travelled to by touching an icon's correspondent Shadow Icon on the Prime Material Plane.
The following areas of Nishnatoba are set aside for House icons:
- An Ancient bone yard - an old bone yard, located on a dangerous slope. Home to the Fist of Oppression of the Ebon Fist.
- The Ancient Garden of Darkness - Home to the Triune Globe of the Sect of the Black Lotus.
- The Carnival's Causeway - a desolate path lined with abandoned carnival fare. Home to the Living Tarot of the Carnivalis Institute of Jestering.
- The Chaos Tundra - a forgotten ruin steeped in snowy, frozen wastes. Home to the Wheel of Chaos of The Occultists.
- The Desolate Glebe - a desolate field, most of the plant-life there is dead. Home to the Crown of Thorns of the Blood Congregation.
- The Forgotten Library - a long-lost repository of maps and atlases. Home to the Stag Crown of the Sentinels of Nature.
- The Garden of Shadows - a darkened garden. Home to the Heart of Shadows of the Shadowsnakes.
- Infernal Temple Ruins - the ruins of a temple that once housed a group of infernals. Home to The Circle of Swords of the Maldaathi.
- The Nest of the Phoenix - the ancient ruins of an arcane complex. Home to the Crucible of Flames of the Warlocks of the Rising Phoenix.
- The Pyramid of Elemental Balance - A four-sided pyramid engraved with elemental runes. Home to the Icon of the Viridian Tome of the Sylvanic Fellowship.
- The Retreat of the Ancient Circle - a forest-locked stand of ancient monoliths. Home to the Verdant Plinth of the Ancient Circle of Druids.
- The Ruins of Castle Proteus - a sprawling castle ruin and courtyard. Home to the Shield of Proteus of the Wardens of the Cerulean Spire.
- The Ruins of Dragonkeep - a defensively-built keep of switchbacks, long abandoned. Home to the Dragon's Eye of the Ashura.
- The Temple Ruins of Arn - a desolate forest across from a fog-covered isle. Home to the Spear of Arn of the Merchants of the Crown.
- The Torrid Wastes - a bleak desert wasteland, scared by the effects of the battles that occurred there. Home to the Icon of the Viper's Tail of the Cult of the Serpent Lords.
The following icon areas have become inaccessible, having had the icon they contained destroyed after what was a long battle in each case:
- The Crystal Tower - the remains of a polyhedral tower. Home to the Crystal Mirror of the Crystalline Circle.
- The Ruins of the Templar - an ancient structure associated with the Templars of old. Home to the Dragon Sceptre of the Guardians of Light.
Note that the following icon areas are still accessible, though the icons that once resided in them have since been razed down:
- The Canyon of the Dawn - a canyon carved out of rough red sandstone. Home to the Triple Suns of the Dawnstriders.
- Daybreak's Cathedral - an abandoned cathedral skirted by darkened forest. Home to the Amber Chalice of the Empyreal Assembly.
- The Monastery of the Ivory Rose - the remains of a crumbling monastery. Home to the Ivory Rose of the Sentaari.