The Tenebrous Cavern is a massive cavern located in eastern Abyssal Depths. This cavern was used as a lair (according to the Horde storyline) by Ozumat until the Horde, using the Verne, forced the creature to leave. The Horde then proceeded to set up a large base camp inside.
The cave entrance is right next to the Lightless Reaches that wraps around the Shimmering Expanse.
After the events of the final quest in the zone, Defending the Rift, all the NPCs remain interactable and do not phase out.
Unlike the other underwater caverns throughout Vashj'ir, players cannot fly in this one.
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