You touch a simple wooden box, imbuing it with magical power. Its surface darkens and gains a metallic green sheen, which remains until the spell is dispelled. A wooden box transformed in this way is called an Echo Box, and the caster of the spell is considered its "owner." Any items that could fit in the box in its original form can fit in it now as well.
While an Echo Box is on the same plane of existence as its owner, the spell cannot transform additional boxes into Echo Boxes. Instead, casting the spell creates an identical duplicate of the original Echo Box. The spell can create a maximum of 1 duplicate at 3rd level, and for every level above 3rd at which the spell is cast, one additional duplicate may be created. If the maximum number of duplicates allowed by the spell's level already exist, the spell fails.
All duplicates access the same space when opened, so items in the original Echo Box also appear in every other Echo Box created by its owner. In the same way, removing an item from any Echo Box also removes it from the original box and all of its duplicates. Echo Boxes never contain items from Echo Boxes owned by another individual.
An action can be taken to touch an Echo Box and dismiss the spell. If the caster is the owner of the Echo Box, and the Echo Box is the original box, the spell ends. All duplicates phase out of existence and are destroyed, and the original box returns to its ordinary wooden form. If the Echo Box is a duplicate, the caster can choose to destroy only that instance of the Echo Box, causing it to phase out of existence, or they can end the spell entirely as if it were the original box.
When an original Echo Box is destroyed, all of its duplicates are also destroyed, and the box's contents are scattered in the Astral Plane.
When a Bag of Holding is placed inside of an Echo Box, a portal to a random location in the Astral Plane opens at the location where the two objects met. All creatures within 10 feet of this portal must succeed a DC 14 Dexterity saving throw or be sucked into it. The Bag of Holding is destroyed, as is the original Echo Box and all of its duplicates (regardless of whether the Echo Box used was the original). Any other items inside the Echo Box are also scattered into the Astral Plane.
Comments