An unassuming bag, that at first would seem to be some sort of cursed object as any object one puts in it disperses after the bag is closed. But those who know how to use it will soon find it's usefulness, as they can fetch any item out of the bag simply by placing their hand in the bag and imaging the object.
After traveling to Limbo the party found themselves in a temple. The temple was protected by a guardian wall-like creature. After defeating it, the party found this item that the guardian was protecting as reward for their efforts.
The Angel which the party encountered claimed a man had come to Limbo via another dimension and built that temple to protect the Bag. Who that man was, or why he felt that the Bag needed to be protected that badly is unknown.
Use in The Vault
The Bag of Holding, while not required to navigate The Vault, is exceptionally helpful as it can hold all the Items that are necessary to successfully venture through The Vault. It is also extremely useful as a container for The Scissors, as it can hold them without activating them.
Though last seen by the party in an unknown ocean, at an unknown depth. It recently washed ashore with the key finding it's way outside of the bag, found by a little Samsaran girl and Kobold boy.