By means of the astral spell, a wizard can project his astral body into the Astral Plane, leaving his
physical body and material possessions behind in the Prime Material Plane. Only
magical items can be brought into the Astral Plane (although nonmagical items could
be rendered temporarily magical through the use of some spells, if the DM
allows). As the Astral Plane touches upon the first levels of all of the Outer
Planes, the wizard can travel astrally to any of the Outer Planes at will. The
caster then leaves the Astral Plane, forming a body in the plane of existence he
has chosen to enter. It is also possible to travel astrally anywhere in the Prime
Material Plane by means of the astral spell, but a second body cannot be formed in the Prime Material Plane. As a general
rule, a person astrally projected can be seen only by creatures in the Astral
Plane.

At all times, the astral body is connected to the material body by a silvery
cord. If the cord is broken, the affected person is killed, astrally and
materially; however, normally only a psychic wind can cause the cord to break. When a
second body is formed in a different plane, the silvery cord remains invisibly
attached to the new body. If the astral form is slain, the cord simply returns
to the original body where it rests in the Prime Material Plane, reviving it
from its state of suspended animation.

Although astrally projected persons are able to function in the Astral Plane,
their actions do not affect creatures not existing in the Astral Plane. The
spell lasts until the wizard desires to end it, or until it is terminated by some
outside means (such as a dispel magic spell or the destruction of the wizard’s body in the Prime Material Plane).

The wizard can project the astral forms of up to seven other creatures with
him by means of the astral spell, providing the creatures are linked in a circle with the wizard. These fellow
travelers are dependent upon the wizard and can be stranded. Travel in the
Astral Plane can be slow or fast, according to the wizard’s desire. The ultimate
destination arrived at is subject to the conceptualization of the wizard. (See
the Planescape Campaign Setting boxed set for further information on the Astral Plane.)

Any magical items can go into the Astral Plane, but most become temporarily
nonmagical therein, or in any planes removed from the Prime Material Plane. Armor
and weapons of +3 or better might function in other planes, at the DM’s
option. Artifacts and relics function anywhere. Items drawing their power from a
given plane are more powerful in that plane (for example, a ring of fire resistance in the Elemental Plane of Fire or a sword of life stealing in the Negative Energy plane).