Sewers of Nihilia, Emanating Crematory

Overview

This instance is reached by speaking with High Priest Diru Riwirn in Barindu as the second step in progression. If you have already completed it or wish to go for xp and random drops you can tell Gamesh "crematory". The walkthrough below is for the progression version. For the Gamesh version you can simply do as you wish.

Mobs in the zone range from 58-62 hitting as high as 900. In addition to the 3 loot dropping rares there are two zonewide drops Larva Skin Cape and Taelosian Runed Girdle.

Make your way to the Furnace Room in the southwest portion of the zone. While clearing your way you will need one person to collect 4 random drops:

When you reach the Furnace Room 4 ghosts spawn and attack; Ngozi, Mabiki, Talakoi, and Yogundi. These hit for about 900 each but can be mezzed. As they are killed they spawn "a ghostly essence" which will slowly path to the crystal chamber in the southeast part of the zone. If they don't spawn try killing the Sewage Slime in the room just east. It is unclear if this is required.

When all 4 ghosts are dead quickly make your way back the way you came and turn south to the crystal room. If you are quick enough you will find Gzifa the Pure One here. Turn in the 4 Remains to complete the expedition and get a character flag.

Rare Mobs

Rare mobs do not spawn until you have killed at least 20 mobs. This is to prevent people from simply spawning instances over and over. All three rares drop Timing Gear for Breakdown in Communications quest.
Cryxtetl
Rare ghost. Can hit as high as 800, but not often. Casts Magician spells.
Drops - Fine Moss-Stitched Gloves, Strange Glowing Stone, Glowing Red Gem of Vengeance
Diseased Larva
Rare worm. Can hit as high as 800, but not often. Nothing special.
Drops - Befouled Neckguard, Slimesnipper Hide Mask, Green Stone of Efficaciousness
Slime Devourer
Rare slime. Can hit as high as 800, but not often. Nothing special.
Drops - Putrescent Chain Helm, Muck-Covered Stone, Chunk of Hardened Slime