Serrel's Confining Sphere

When this spell is cast, it creates a magical, transparent sphere of force around the item or creatures specified by the caster. Half the sphere is above the ground, the other half below. The sphere can be used to entrap a creature or to protect something. If the sphere is cast upon an unwilling creature, a successful saving throw vs. spell allows the creature to escape the area of effect; no other condition allows a saving throw against this spell.

The sphere is immobile, and no solids, liquids, or magically-created gases can pass into or out of it. In addition, spells cannot be cast into or out of Serrel's confining sphere, nor do spell areas of effect penetrate the barrier. The sphere is immune to dispel magic and disintegrate spells. However, the sphere can be destroyed before the expiration of the spell by any of the following means:

A properly worded limited wish or wish

A rod of cancellation

A cube of force, set against all things, that is triggered inside the sphere

A weapon of +4 enchantment or better that inflicts 50 or more points of physical damage on the sphere in a single round

A sphere of annihilation.

The material components are a small quartz sphere and a lump of earth.