|The Slave Pens (5)|
|The Underbog (5)|
|The Steamvault (5)|
|Serpentshrine Cavern (25)|
Underbog is the 2nd 5-man instance within the Coilfang Reservoir found on the east side of the naga invested complex. The Underbog is home to the last vestiges of natural life left within Coilfang Reservoir that has not been completely stamped out by the Naga incursion. The only Naga presence in this section defends the structure they built to house their hydra god, Ghaz'an. The rest of the Underbog is a natural habitat, home to the most powerful species of animal life in Zangarmarsh.
- Main article: Coilfang Reservoir
Here, concealed by the cold fathoms, Lady Vashj's naga ply their resources - the exotic flora and fauna of the cavernous Underbog, the Broken who toil in their claustrophobic Slave Pens, and the arcane machinery they've constructed in the Steamvault - towards a catastrophic goal set forth by Illidan the Betrayer. Unopposed, they will drain Zangarmarsh's waters, and claim dominion over the dry bog that remains.
Coilfang Reservoir is the name for a naga-dominated compound that lurks under Zangarmarsh's deepest waters. The reservoir, punctured throughout by massive open pipes and pistons, seems big enough to house armies - and, yet, its purpose isn't strictly military.
- Main article: Underbog mobs
- Main article: Underbog loot
On normal, it will give approximately 1100 Cenarion Expedition Reputation through Friendly, and it also gives ~3300 Sporeggar reputation through exalted. Heroic mode will give approximately 2600 rep with Cenarion Expedition through exalted, but no longer give reputation with Sporeggar.
- See also: Removed Underbog quests
- The was once needed to unlock the Heroic Difficulty.
- Patch 4.3.0 (2011-11-29): New quests added.
- Patch 4.2.0 (2011-06-28): removed.
- Patch 2.0.3 (2007-01-09): Added.