The Underspace is a series of tunnels through subspace that reach throughout parts of the Delta Quadrant.
- Until their defeat by a coalition of races in the 15th Century, the Vaadwaur were masters of Underspace and used it to control their conquered territory. After their defeat, the Turei took control of Underspace and would take any action, sometimes hostile, to prevent other races from using the Underspace tunnels.
- In 2376, the U.S.S. Voyager would briefly become trapped in Underspace, leading to first contact with the Turei, who attempted to board the ship to seize or destroy any sensor readings of Underspace. Taking refuge on a nearby planet, the crew of Voyager discovered the Vaadwaur in stasis. After being awakened by Seven of Nine and defeated by cooperation between Voyager and the Turei, the Vaadwaur escaped into Underspace.
- At some point over the following decades, while exploring Underspace looking for a way to restore his people's power and glory, Gaul, the leader of the Vaadwaur, would make contact with servants of the Iconians.
- In 2410, the resurgent Vaadwaur would make the Turei a primary target for their knowledge of Underspace in an attempt to reclaim it as the Vaadwaur's own.
While the extent of Underspace remains a secret closely guarded by both Vaadwaur and Turei, there are known to be access points in certain systems.
- “Wyanti System Patrol”: When the Turei thieves escape through Underspace, the player's ship pursues.
- “Takedown”: During the Delta Alliance's assault on Vaadwaur Prime, the Turei are assigned to secure Underspace to prevent the Vaadwaur from escaping or bringing in reinforcements.
- It is currently unknown if there is any relation between the subspace tunnels in the Delta Quadrant that form Underspace and the subspace tunnels recently discovered in the Beta Quadrant due to Tholian activity, including whether they are merely separate, but similar networks or if they are actually part of a galaxy-wide system of tunnels.
- The Azure Nebula, location of other subspace tunnels.
|Details||Turei • Turei System • Underspace|
|Ground Forces||Turei Ensign • Turei Lt • Turei Commander|
|Starships||Turei Frigate • Turei Cruiser|
|NPCs||Bellas • Norrick • Stil|
|Details||Vaadwaur Supremacy • Vaadwaur • Vaadwaur Prime • Kartella Prime • Underspace|
|Ground Forces||Vaadwaur Scout • Vaadwaur Soldier • Vaadwaur Tech Soldier • Vaadwaur Commando • Vaadwaur Tech Commando • Vaadwaur Tech Officer • Vaadwaur Overseer • Heavy Mortar|
|Starships||Vaadwaur Assault Vessel • Vaadwaur Scout Vessel • Vaadwaur Assault Cruiser • Vaadwaur Interdictor Cruiser • Vaadwaur Heavy Artillery Vessel • Vaadwaur Juggernaut|
|NPCs||Eldex • Galik • Gaul • Mengin • Relin • Telen|
|NPC starships||Eldex's Ship • V.S.W. Implacable • V.S.W. Vozroz|