Great Furnace

Main universe
In the main matoran universe, it was the hottest furnace of all Metru Nui. The toa Metru also battled the Morbuzahk here.

Regin of fear
In the Regin of fear alternate universe, the Great furnace was transformed into a prison. After they were captured by the Vahki in the archives, Antroz, Krahka, Keetongu and Savage were imprisioned here. Although, they scaped, and the furnace was severally damaged when Savage went on a mad rampage. He fired a rocket at some Krahli, making the platform he and the Vahki were to fall to the lava. Savage was saved by Keetongu.

Appareances

 * Regin of fear