The Hollow
Where the earth breathes poison and monsters dwell in the dark.
In the depths beneath Sera's fractured crust, 'The Underworld' is the canonical term for the vast, subterranean network created by Imulsion deposits and expanded by Locust engineering. These dark, labyrinthine spaces serve as the primary habitat for the Locust Horde and later the Swarm, functioning as both breeding grounds and strategic fortresses hidden from surface view. While not always a singular, named location on official maps, The Underworld represents the terrifying underground network that defines much of the war's history.
- Type
- Subterranean Network / Imulsion Cavity
- Inhabitants
- Locust Horde, Swarm, Lambent (Historical)
- Primary Resource
- Imulsion Deposits
- Status
- Active / Contested
Lore & Background
Throughout the conflict following E-Day, these tunnels remained active and accessible to the Locust Horde, serving as their primary stronghold until the final assault on the Underworld. Contrary to belief, the COG did not seal off this entire network; while Emergence Zones were contained, the Locust maintained control over their excavated domains. The Lambent plague later mutated within these spaces, turning them into toxic death traps where light could not penetrate and sanity was lost to the hum of the infection. In modern times, remnants of these networks still pose a threat, often inhabited by feral Locust or Swarm minions waiting for an opportunity to breach the surface again.
In Their Own Story
The air down here tastes like rust and old blood. Kait adjusted her helmet light, the beam cutting through dust that hadn't moved in fifty years. The walls weren't rock anymore; they were slick with black sludge that pulsed faintly. She heard a skittering sound above—too heavy for a rat, too quiet for a man. This was where the war never ended. In the Hollow, time didn't pass; it just waited.
Reader's Guide
Survivors should treat any mention of The Hollow with extreme caution. These areas are unstable due to Imulsion erosion and often lack structural integrity. Locust or Swarm activity is highly probable in uncharted tunnels. Standard COG weaponry may be less effective against heavily armored variants found deep underground. Navigation is nearly impossible without specialized equipment, as the magnetic interference from Imulsion deposits disrupts compasses and comms. Historical data suggests these networks connect to major surface cities via hidden shafts, making them potential invasion routes.
Did You Know?
- Imulsion seepage is the primary cause of natural cave collapses known as hollows.
- The Locust used these spaces to store massive amounts of fuel for their tankers.
- Lambent infection spreads faster in enclosed subterranean environments due to gas concentration.
- The majority of The Underworld was excavated by the Locust Horde over millennia, rather than being natural formations existing since Sera's creation.
More in Lore & History
Elsewhere in the Gears of War universe
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