The Chest of the Ebony Sage

In the early days of what would become the Dracanomachi, while Apep was tearing her way across the land in an effort to extract vengeance against anyone that could have murdered her brood-sister and her judges were creating much of the initial real cracks of instability in the Old Imperium, there coaleses a description of a particular artifact. There are no sources that refer to it directly, leaving many of the assumptions of the item in question highly suspect.
I have taken to calling it the Chest of the Ebony Sage, after the description of the person carrying it, and all the hells seem to follow with it.

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There are many artifacts out there just waiting to be found, especially after the Dracanomachi and the collapse of the Old Imperium, and their effects are extensive. Weapons, medicines, staves that construct rudimentary shelter at a thought, amulets that absorb all light, and everything in between. Most have some sort of record. The mage or crystal smith that made it, or the hero or general that held it aloft.
The Chest of the Ebony Sage, however, stands out for the lack of context for its existence and its function. No one is credited with its creation, and the Great Wyrm Apep has never spoken of it on record, despite it appearing within her wake with regularity. Is it truly something she knows nothing about, or some great secret? The possibility remains that the Ebony Eyed wyrm being related to the Chest is a coincidence of color, improperly attributed over the centuries. 
Its method of operation and end result also remain equally mysterious, though the Chest seems a tool of great destruction for the places it appears within and around tend to disappear from the historical record in short order.

By all physical descriptions, the Chest is small enough to be carried in two arms, and constructed from a dark wood without any major adornments. It's not even clear if it has any sort of latch or locking mechanism, just that it can be opened by the carrier.