Bag of holding
A bag of holding is a fictional magical item in the Dungeons & Dragons roleplaying game, capable of containing objects larger than its own size. Since its introduction, it has appeared in other media.
A bag of holding appears to be a common cloth sack of about 2 by 4 feet (0.61 by 1.22 m) in size. It opens into a nondimensional space (similar to a magic satchel) or a pocket dimension, making the space larger inside than it is outside. Each bag of holding always weighs the same amount, between 15 and 60 pounds (6.8 and 27.2 kg), regardless of what is put into it. It can store a combined weight of up to forty times its own weight, and a combined volume of 30 to 250 cubic feet (0.85 to 7.08 m3). A living creature put in a bag of holding will suffocate after about 10 minutes.
If a bag of holding is overloaded, or if a sharp object pierces it (from outside or inside), the bag will rupture and be ruined, the contents lost forever in "nilspace".
Other magical bags similar to the bags of holding include:
Some bags outwardly indistinguishable from a bag of holding have highly undesirable qualities. They are created by spellcasters either purposefully (especially in the case of a bag of devouring), or as a result of a failed spell in the process of creating a bag of holding.
Essentially a bottomless pit in a bag, this bag appears to be a normal sack, like a bag of holding, and seems to be a bag of holding on closer inspection. However, the bag is a lure used by an extradimensional creature; it is one of its feeding orifices. Issue 271 of Dragon featured an article titled "The Ecology of a Bag of Devouring" that discussed the nature of such a creature.
Any substance of animal or vegetable matter put into the bag has a chance of being swallowed over time. Even a person reaching in to retrieve or place an item, after the initial time, has a chance of being completely dragged into the bag and swallowed. The bag of devouring will act as a bag of holding, but every hour it has an increasing chance of swallowing the contents. Any plants or animals swallowed by the bag in this way are transported to the creature's stomach, digested, and lost forever, while inedible items are swallowed and spat into another plane.
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