Wondrous item, rare (requires attunement)
The lantern has 3 charges and regains all of them at dawn. It must have a lit candle in it to work at all. As an action you can open the horn shutter and expend 1 charge. For 1 minute the lantern sheds light in a 20-foot radius, and in that light you see what stood in the lit place one hour ago: creatures and things, pale and without colour, moving as they moved, making no sound.
You see nothing of the present in that light. While the shutter is open, creatures and objects now in the area are lightly obscured to you, and you have disadvantage on Wisdom (Perception) checks that rely on sight.
What the light shows cannot be touched, spoken to, or turned aside. A thing that was carried through the area an hour ago is shown crossing it and is not followed out. A creature that was invisible an hour ago is invisible in the light. Any other creature that can see the light sees the same hour you do.
Closing the shutter ends the effect early. The lantern shows no other interval than the hour. The interval has been tried against a clock, in this hall, and it does not move.
Source: Provenance — The Quist Sale