The Mark of the Erasure, also known as the Mark of Erasure, is a region in the northwestern part of Hieron. As its name suggests, it bears signs of impact from the Erasure cataclysm. Because details of the cataclysm are hitherto ambiguous, so too is the Mark's exact nature.
Algid Pinelands
The Algid Pinelands, which surround the Mark of the Erasure, are cold and snowy in a way the local climate shouldn't be, and become colder and more inhospitable the closer one gets to its center. Goblin societies here known as the Nameless were once ravaged by word eaters. The snow elf village of Auniq is located here.
The Tower of Samot
At the center of the Mark of the Erasure is the ruins of a once-massive tower of Samot. Paradoxically, weather at the very center is balmy and warm compared to the raging snows that surround it. The various parts of the ruins are gateways to alternate worlds.
In the Tower of Severea map room, this tower was marked with a green plumbob crystal.
Kindrali reveals that the Tower of Samot was built as part of a massive military-driven industrialization effort, likely to do with Samot's war with Samothes and Samot's research towards the Heat and the Dark. It encompassed an entire city within a single tower. There, mages researched alternate futures, several of which are visited by Ice Party in the ruins of the tower.
The mirror in the Tower of Samot is one of five artifacts of power.
Denizens
The area, whilst thought uninhabitable by much of Hieron, is home to the snow elves, goblins, owlbears, various flora and fauna, and at least one breed of dog.
The Mark of the Erasure
Clues throughout the series indicate that the Mark of the Erasure is linked to the creation of Ordenna. This is later confirmed: mages from the Tower of Samot used the land around the tower in one of their numerous experiments researching the Heat and the Dark, causing an immense magical incident that transferred the land from there to the northwest of Hieron, creating the islands of Ordenna and destroying the tower. The experiment also imbued the land with the Dark, resulting in the creation of Ordennan Steel.