Plane shift

Plane shift was an alteration or conjuration spell that transported the caster and a few others to a different plane of existence.

Effects
By means of this spell, the caster and up to seven other beings could be transported to a chosen plane or alternate dimension, including specific layers of multilayer planes. Willing subjects had to form a circle with the caster, holding hands or otherwise maintaining physical contact while the spell was being cast. The caster could also choose to send a single subject to a random location on another plane, but if the subject was unwilling, the caster had to successfully touch the target and the victim had a chance to resist the magic of this spell.

The earliest version of this spell was quite accurate, placing the travelers at a specific location if desired. Later versions had problems with accuracy,  with one version having a maximum error of 500 miles (800 km).

Components
In addition to verbal and somatic components, the key to casting this spell was a forked metal rod of a certain size and composition that attuned it to the desired destination plane. In some schools of thought, the size and metal type of the rod were crucial to guarantee the correct destination was reached,   but there may have been other ways to attune a given rod to a specific plane.

Planar Forks
The following table details the forks known to access most planes. Material is the substance out of which the fork was made, usually metal. For example, in general, gold led to upper planes, while iron led to lower planes. Pure metals were used for inner planes, while alloys of those metals led to the respective paraelemental planes.

Pitch is the single note to which an individual fork was tuned. If a plane had layers, this note always led to the first layer of that plane. Quasi-elemental planes could be reached by using a fork tuned sharp for positive planes and flat for negative planes. Chord, in the table, indicates that multiple forks were required to ring in harmony. Major chords usually took one to the second layer of a plane, while minor chords took one to the third layer. More complicated harmonies were rumored to be able to reach other layers.

History
In the time of ancient Netheril, divine spells were considered to come from the breath of gods and called "winds". This spell was classified as being a Transcendent wind.