The Spirit Realm

Not to be confused with the Shadow Realm, a related anomaly that appears to be another dimension of Super Mario 64, and the apparent equivalent of Hell.

The Spirit Realm is an anomalous area found inside of some copies of Super Mario 64, only discovered after the Shadow Realm's Disappearance event. It has been described as a white, sky-like area made up of clouds that reportedly contains warps to levels that met the requirements to be warped to the Shadow Realm; Either being deleted, or marked as a joke, dubitation, non-canon or Ztar article on the Wiki known as MIPS Hole, now apparently fully intact, as opposed to the Shadow Realm only holding parts of the levels. It is believed that the Spirit Realm is the new version of the Shadow Realm, and the equivalent of Heaven, as opposed to the Shadow Realm being the equivalent of Hell. The level can reportedly be accessed through the same method as the Shadow Realm, being inside of a level as it meets the requirements to be found in the Spirit Realm, though a new method has reportedly been found by using the Wing Cap in the Castle Grounds to fly into the sky to be warped into the Spirit Realm.

Description
The Spirit Realm's geography is described as rather simplistic, being made up of several clouds in a large white void that lead to several portals to levels that would have entered the Shadow Realm, now fully in-tact and playable. Due to the amount of levels that can be found in the Spirit Realm, they will not be covered in specific. Notably, a specific portal has been reported that would lead into a new form of the Shadow Realm that appears as an inverted version of the Spirit Realm, now with no level assets or portals, rendering the area useless and simply another explorable region. Notably, some people had reported a portal being found in the Shadow Realm before the Disappearance, potentially being the portal to the Spirit Realm. Why the Shadow Realm was reduced to such a state, practically being another regular level in the Spirit Realm, is unknown.

Theorizing
It is believed that the Spirit Realm was created by the unknown force manipulating MIPS Hole and the Personalization A.I. of Super Mario 64 and/or user VentureSonic in order to replace the Shadow Realm as "MIPS Hole's trash bin." Why this was necessary is unknown, though a plausible theory is that with no other place to go to after the collapse of the Shadow Realm, the levels that would have been warped there instead began to leak into the real world, requiring a new location for them to warp to, thus causing the Spirit Realm's creation. However, this does not explain how the levels suddenly became in tact or why the Shadow Realm still exists.