World Tree cosmology The World Tree cosmology model was outlined in the Year of Wild Magic , 1372 DR , and quickly became the most widely accepted model during those tumultuous times , supplanting the Great Wheel cosmology . The name came from the discovery of a sentient being that manifested itself as a brobdingnagian tree that connected various planes of existence , much like the river Styx . The World Tree cosmological model was invalidated by the Spellplague in 1385 DR and the decade that followed , during which the Elemental Planes collapsed into the Elemental Chaos , the Ethereal Plane and World Tree were destroyed , and the Outer Planes that survived became drifting dominions in the Astral Sea as described by the World Tree model ' s successor , the World Axis cosmology model . Basic Structure . The Inner Planes , also known as the Elemental Planes plus the Energy Planes , made the transition from the Great Wheel model to the World Tree model almost intact , the major difference being that they were connected to the Prime Material Plane via the Astral Plane instead of the Ethereal Plane . The Outer Planes underwent extensive rearrangement , increasing in number from seventeen to twenty one to twenty six , and severing nearly all interplanar connections except those to the Prime . Thus the connection map could be said to resemble a tree , with the Prime Material Plane being the trunk with roots " descending " to the Inner Planes and branches " ascending " to the Outer Planes . No longer arranged strictly by alignment , the Outer Planes were grouped into three categories based on being predominantly Good , Neutral , or Evil , regardless of the influences of Law or Chaos . The three categories were the Celestial Planes ( good ) , Neutral Planes ( neutral or unaligned ) , and the Fiendish Planes ( evil ) . Two more planes were discovered that also connected to all the Outer Planes : Cynosure and the Fugue Plane . Only deities could pass through the astral " portals " from their realms to Cynosure and back to their home plane . The Fugue Plane was where the souls and spirits of the dead congregated , awaiting judgment or transport to the domain of their primary deity . Only divine , demon ic , or devil ish servants of the gods could use the portal from their realm to the Fugue Plane for the purpose of guiding , stealing , or bargaining with souls to take them back to their eternal reward or damnation . The Plane of Shadow was upgraded from a demiplane to be coexistent with the Prime Material Plane , touching it at all points just like the Ethereal Plane , allowing rapid travel between distant destinations on the Prime . It was believed that the Shadow Plane also connected the Prime to other Material Planes , such as Oerth for example . An adventurer ' s journey to another plane of existence was typically accomplished by means of an " astral projection " , " plane shift " , or " gate " spell . " Astral projection " was considered the safest mode of exploring because one ' s physical body was left behind in a ( hopefully ) protected location while their astral self traveled through the mostly barren Astral Plane to a " color pool " that was the door to their destination . Upon arrival , a new physical body was formed out of the materials of the destination plane and this new body was therefore immune to any pervasive environmental hazards . ( On the Elemental Plane of Fire a body might be formed out of elemental fire , magma , and brimstone , for example . ) In contrast , " gate " and " plane shift " transported one ' s body and possessions directly into possible peril . Travel between one Inner or Outer Plane and another without passing through the Material Plane was either difficult and dangerous or impossible without involving the mercurial gods and their servants . Deities could maintain astral portals between their realms and those of other agreeable powers , but these were usually not for mortals to use . Two cross - planar features existed that could be used to journey between some of the Outer Planes . First was the World Tree itself , a sentient " tree " on a cosmic scale that joined all of the Celestial Planes together , much like Yggdrasil the World Ash connected Gladsheim to Hades in the Great Wheel cosmology model . The World Tree did not tolerate intruders unless they had a good and noble reason for using it as a celestial shortcut . The other feature was the River of Blood which coursed through all the Fiendish Planes except for the Supreme Throne and the Demonweb Pits in a fashion similar to the river Styx which flowed through all of the Lower Planes in the Great Wheel model . All manner of evil creatures swam in the river , lurked on the banks , piloted craft on the surface , or patrolled the skies above the River of Blood looking to catch anyone brave or foolish enough to navigate the deceptively smooth waters . And just like the Styx , any mortal immersed in the river immediately lost all memories . Coterminous , Coexistent and Transitive Planes . Coterminous planes were linked at one or more points where travelers could cross over without the aid of magic . Two or more planes were coexistent if they overlapped completely , allowing movement by some ( usually magical ) means from one to the other at any point . They were also sometimes referred to as parallel planes . Transitive planes were simply used as a conduit or passageway between two planes ( or two points on the same plane ) that were each coterminous with the transitive plane . A plane could be both coexistent and transitive . Outer Planes . The terms Inner and Outer Planes originated with the Great Wheel cosmology model when the structure of the cosmos was seen as a series of somewhat concentric spheres and the names continued to be used in the World Tree model . The Outer Planes were divided into three distinct groups mainly based on the Good , Evil , or Neutral alignment of their inhabitants . Some of the Outer Planes had multiple layers that were coterminous with their neighboring layers , usually at very high or very low elevations giving the impression that they were stacked like tiers . The Astral Plane connected to all layers of a plane if there was more than one ( however , see House of the Triad and Nine Hells below ) , whereas the " plane shift " spell always targeted the first layer of the destination plane . Celestial Planes . The Celestial Planes were the home of deities and beings that were fundamentally Good in nature , word , and deed . Each of the Celestial Planes were connected to the Prime Material Plane by a branch of the Astral Plane . Additionally , each of them was coterminous with at least one " neighbor " via the World Tree , which could be used as a " back staircase " with the Tree ' s permission or tolerance . The roots reached into Arvandor and Dwarfhome from the trunk , which touched Brightwater , the Golden Hills , and the House of Knowledge . Extending from the trunk were branches to Dweomerheart , the House of the Triad , and Green Fields , with the top of the Tree terminating in the Gates of the Moon . Fiendish Planes . Deities and entities of the Evil persuasion inhabited the set of planes known as the Fiendish Planes . Separate branches of the Astral Plane connected each of them to the Prime Material Plane and most of them were also coterminous with one or two neighbors via the River of Blood ; the only exceptions were the Demonweb Pits and the Supreme Throne . The River of Blood was thought to originate in the Abyss and flow in order through Blood Rift , the Nine Hells , the Barrens of Doom and Despair , Clangor , Fury ' s Heart , Hammergrim , Nishrek , and the Deep Caverns before cascading into the Fated Depths . Neutral Planes . There was also a group of planes whose inhabitants did not adhere strictly to either good or evil , or tolerated the presence of opposing alignments . The Neutral Planes , sometimes called the Unaligned Planes , were connected to the Astral Plane in the usual fashion but were host to neither a branch of the World Tree nor a channel of the River of Blood . Cynosure and the Fugue Plane . In the World Tree cosmology model there were two planes that , from a mortal ' s point of view , existed outside the model , disconnected from the Astral tree structure , but still played very important roles in the afterlife and the struggles between the Powers . Inner Planes . The Elemental and Energy planes contained the building blocks of the multiverse . Each plane was beautiful and deadly in its own way and was inhabited by strange and unique creatures . The mode of travel to the Inner Planes changed from ethereal in the Great Wheel cosmology to astral : travelers no longer had the capability of moving through the Border Ethereal before selecting an entry point . Instead they viewed their destination through a " color pool " in the Astral before passing through it to arrive on the new plane . The four Elemental Planes and two Energy Planes were no longer directly connected nor did they form para - and quasi - elemental planes as they did in the older model . The concept of the Elemental and Energy Planes being at the " root " of the tree - like Astral Plane was common , but since all paths lead through the nexus of the Prime Material Plane it was really just a matter of perception . Along with the advent of the World Tree cosmology model was the introduction of planar traits to describe all the types and characteristics of planes and layers . The Inner Planes themselves were mostly unchanged from the Great Wheel cosmology model , the major difference being that time no longer moved twice as fast on the Inner Planes than on the Prime Material Plane . In the terminology of planar traits , the Great Wheel model used the Flowing Time trait with 1 true day equaling 2 subjective days , and the World Tree model used the Normal Time trait . Elemental Planes . In this cosmology model , before the Spellplague , the Elemental Planes were individual infinite planes of almost pure elemental substance . The most powerful beings on these planes were called Elemental Lords and were worshiped as deities in a few places on Toril . After the Spellplague they were revealed to be primordial s . Energy Planes . The Positive and Negative Energy planes were the source and drain , the push and pull , of life and death . Extremely inimical to mortal life , only the minor - dominant areas could be inhabited and they were in constant danger of being overwhelmed by a major - dominant flux . The Negative Plane drained all energy while the Positive Plane was pure energy in such abundance that mortal forms could not contain it . During the Spellplague all the Elemental and Energy Planes merged into the Elemental Chaos , but the goddess Shar folded part of the Negative Energy plane into the Plane of Shadow , forming the Shadowfell .