A sphere of shimmering force encloses a Large or smaller creature (Concentration, 1 min). Target makes a DEX save; on a failure it is enclosed. The sphere is immobile, lasts until the spell ends, and nothing can pass through it. The enclosed creature can use an Action to roll the sphere at up to half its Speed, but can't attack or be attacked. It can't be moved by other means except Disintegrate.

Material: a hemispherical piece of clear crystal and a matching hemispherical piece of gum arabic