Bead of Force

This sphere of black glass is ¾ an inch in diameter and can be thrown up to 60 feet as an action. On impact it creates a 10-foot radius explosion. Creatures in the area make a DC 15 Dexterity _saving throw_ , taking 5d4 force damage on a failure. A sphere of force then encloses the same area for 1 minute. Any creature that is completely in the area and fails its save is trapped within the sphere. Creatures that succeed on the save or that are only partially within the area are pushed away from the point of impact until they are outside the sphere instead. The wall of the sphere only allows air to pass, stopping all other attacks and effects. A creature inside the sphere can use its action to push against the sides of the sphere, moving up to half its Speed. The sphere only weighs 1 pound if lifted, regardless of the weight of the creatures inside.