Earth node

An earth node was a geological anomaly usually beneath the surface of Faerûn.

Description
An earth node was a collection or stream of magic that existed mostly in the Underdark. As a general rule, the bigger the affected area of a node was, the stronger was the magic that could be harnessed from it. About half of them were very weak areas whose strength was more less the same within the area, but the other half was made like an onion. They had layers of magical power that became stronger the more one went towards the origin of the node and, as one got close, more magical power could be harnessed. There was no rhyme or reason to where they sprung up. It was entirely possible for an earth node to exist within solid rock, for example.

Those creatures in tune with arcane magic could sometimes sense the presence of a node. The power field of nodes varied from approximately 30 feet (9 meters) to 1/2 mile (0.8 km.)

These power fields were invisible, but the area these fields existed in were often beautiful and/or bizarre sights. For example, giant geodes or a strangely regularly shaped cavern were forms such an area could take.

Uses
An earth node could be used to increase the strength of spells or to gain additional spells by those who were adept at node magic. Earth nodes were special among nodes for the spells they granted were more predictable. Naturally, some exceptions existed, but said spells were in order of strength: node lock, soften earth and stone, node door, stoneskin, wall of stone, move earth, earthquake, excavate, and the earth elemental-version of the elemental swarm spell.

A truly unique power of an earth node was the one to use it as a cache. This power was only open to those who were trained in node magic. It allowed the user of node magic to magically store something into the earth node, the object than disappeared, and allowed the user to take the object from any earth node on Toril. The stronger an earth node was, the more objects could be stored inside it. If it was already full, the user did not necessarily know what was stored inside but could try to retrieve the goods.

Earth nodes were very susceptible to physical changes of the area they existed in, physical changes could easily cause them to erode their magical properties. As mentioned above, earth nodes were magical phenomenon that appeared wherever they appeared without regard to accessibility. Excavating such an area required not only mundane skill but also magical skill to keep the magical properties safe.

Some arcane casters were able to tap into the power of a node and occasionally nodes could be used as teleportation devices. Some arcane casters also used them to cast rituals tied to the earth node.

Deep diviners were spellcasters who specialized at using earth nodes.