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The Numidium or Anumidum, the Brass God, was a gigantic golem of Dwemer origin. Constructed by Tonal Architect Lord Kagrenac, Numidium was directly related to the disappearance of the Dwemer, and since then has been resurrected several times.
By the end of the Second Era, the Morrowind Tribunal had possession of Numidium. As a tribute to the Empire, the Tribunal gave Tiber Septim the golem. The Numidium was first reactivated by Tiber based on Zurin Arctus' Dwemer research. Reactiving the Numidium required a replacement heart, for which the Mantella was used, a soul gem that mimicked the properties of Lorkhan's Heart when filled with the soul of a Shezarrine. The golem was controlled by a Totem that can only be wielded by those of royal blood or great power.
The Numidium proved very effective in bringing down the mighty Aldmeri Dominion and conquering Tamriel in 2E 896. The official records tell a story wherein after defeating all his enemies, Tiber Septim used the Numidium to destroy the neutral royal families of Tamriel so that he could enthrone persons he knew to be loyal. The Underking, another Shezarrine who was confused for Zurin Arctus due to their shared soul, disagreed with this use of the Numidium, and tried to reclaim the Mantella. However, the process devastated both Numidium and the Underking. The heart they shared was blown into Aetherius. Pieces of the Numidium were scattered throughout Tamriel.
In the centuries that followed, Septim's elite soldiers were tasked with collecting the pieces of the Numidium. These soldiers became known as the Blades. During the reign of Uriel Septim VII, both the Numidium and the Totem were found in the Iliac Bay region. This nearly set off a civil war amongst the dozens of independent city-states in the region, beginning with the murder of King Lysandus of Daggerfall. Ultimately, an anonymous hero traveled to the plane of Aetherius to recover the Mantella, then returned to Mundus and activated the Numidium.
The Elder Scrolls (C) Bethesda
The moons (Masser and Secunda) are not drawn by me; they are images by bethesda inserted in