To find the Taken Altar in Eris Morn's apartment in Destiny 2, which is needed to offer Metastasized Essentia, follow these steps:
: The Taken Altar is located in Eris's apartment in the Last City1. Specifically, it’s tucked between the bookcases and a room divider1.
: The altar is a strange-looking totem with a dark orb inside1. It looks like a small stone pillar with a black orb in it3.
: You need a total of 10 Metastasized Essentia to make an offering at the Taken Altar1. In exchange, you will get 10 Essence of Desire, some gear, and 200 Rep for the Slab23. The rewards you receive from the altar can vary, ranging from powerful legendary weapons to valuable currency and rare materials1.
: Metastasized Essentia can be found in the Nether5. To successfully obtain the resource, you need to complete the Nether activity without using all your wipes and being returned to orbit5. Until you complete the Nether activity, the Essentia in your inventory will be "Fleeting" and disappear if you wipe to orbit5.