Demiplanic orb (5e Equipment)
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Wondrous Item, very rare (requires attunement)
A smooth glass ball, roughly the size of a palm. When rubbed, a reflection of the demiplane inside is shown.
As an action, you can throw the orb up to 30 feet, causing it to shatter as a portal to the inside demiplane appears where the orb shattered, as a 10 foot wide circle. The demiplane is a 30 foot hollow square, with walls of smooth stone. The portal dissapears after a round, as the orb reforms.
If thrown at a creature, they must make a DC 18 Dexterity saving throw, or be pushed into the demiplane.