According to the Per Historia Arcandor Materia this legendary hammer once belonged to Damian Krale, a cleric of Shar. It was gifted to him to use as her protector in the material plane. It is said to be one of the only items on the material plane that can craft magic items with Shadow Magic. It is also mentioned as having originally housed the Shadow Stone, but with Shar granting Krale a new weapon, it is currently presumed the stone moved to that item, as that was the source of Krale's power.
In the Historia, the original entry describes the hammer, but the illustration shows it without eyes. It seems that these are a new addition to the hammer but who, or when, these were created, remains to be discovered. The Maybesitters found the Remnant being used by the Shadow Smith in the heart of the volcano on Mintarn, being used to repair the broken blade, Godsbane.