Such nexuses could be caused by any number of different events. Korriban in general and the Valley of the Dark Lords specifically were nexuses of the dark side of the Force due to the long-term presence of the Sith Lords, Nam Chorios was a nexus of the Force due to the omnipresence of the Tsils, a form of life; Vjun was a nexus of the dark side due to the horrible events of its past, the Dark Side Cave on Dagobah and a spot in orbit over Endor were tainted by the death of dark side users, Byss was a nexus of the dark side of the Force because it housed Palpatine's clones and his various Sith alchemy experiments and the Force energies sucking the lives on the planet.
The natural mountain on which the foundation of the Jedi Temple on Coruscant rested was a nexus. This became tainted by the dark side with the defeat of Lord Nyax at the site of the ruined Temple during the Yuuzhan Vong War. The most powerful nexus was the Valley of the Jedi, where the spirits of several thousand Jedi, both light and dark, were trapped after the Seventh Battle of Ruusan, a perhaps limitless source of Force energy even after the spirits were freed.
- "Anakin sensed that they were closing in on something powerful and evil ... and believed it to be the [Sith] Holocron.
Anakin got to his feet and moved toward the pilot's seat. It was almost time to bring the ship out of hyperspace. Sitting down at the controls, he suddenly felt a ripple in the Force. He quickly brought the ship out of lightspeed. The familiar starriness of space came into view around him...
Obi-Wan was beside him in an instant. "I felt a wave in the Force," he said."
- ―13-year-old Padawan Anakin Skywalker and his Master Obi-Wan Kenobi feel a "ripple" or a "wave"—sense dark rhythms—in the Force en route to the planet Ploo II to reclaim the Holocron of King Adas from the hands of a dark side fanatic.
Objects left in the presence of a Force nexus for extended amounts of time eventually became saturated with the Force, which imbued the object with special abilities, like an edge that will never dull, the ability to absorb some Force powers like Force lightning and electric judgment, or even the ability to enhance the wielder's perception of time, allowing him to think and react faster than otherwise possible. This effect allowed even a being who wasn't Force-sensitive to use the weapon to a great degree. Further, objects (such as a holocron) imbued with a particular aspect of the Force—be it light or dark—could actually become so saturated as to make their very presence intolerable to those of opposite alignment.
In 29 BBY, Obi-Wan Kenobi and Anakin Skywalker encountered a nexus of powerful dark side energies in an underwater geyser crater on the planet Kodai, where the ancient Sith Holocron of King Adas was hidden. The strong underwater nexus was perceived even with the evil artifact having been stolen from its burial place. As the Jedi duo pursued the holocron's thief through hyperspace, its dark energies were again perceived as a powerful "ripple" or "wave" in the Force, causing the Jedi to quickly exit hyperspace to investigate.
Behind the scenes
The first Force nexus to appear in Star Wars continuity was the cave on Dagobah, seen during Star Wars: Episode V The Empire Strikes Back. The concept of a location imbued with Force energy was then expanded on in the 1997 video game Star Wars: Jedi Knight: Dark Forces II.
- Star Wars: Tales of the Jedi
- Tales of the Jedi (audio)
- Star Wars: Tales of the Jedi - Dark Lords of the Sith
- Tales of the Jedi: Dark Lords of the Sith (audio)
- Star Wars: Knights of the Old Republic
- Star Wars: Knights of the Old Republic II: The Sith Lords
- Star Wars: The Old Republic
- Darth Bane: Dynasty of Evil
- Darth Bane: Dynasty of Evil audiobook
- Darth Plagueis (Mentioned only)
- Darth Plagueis audiobook (Mentioned only)
- Echoes of the Jedi
- Star Wars Galaxies: An Empire Divided
- Star Wars: Episode I The Phantom Menace
- Star Wars: Invasion of Theed Adventure Game (Adventure 5: Renegade)
- Jedi Apprentice Special Edition: The Followers
- Star Wars: Episode II Attack of the Clones
- Star Wars: Episode III Revenge of the Sith
- Domain of Evil
- Star Wars: Episode V The Empire Strikes Back (First appearance)
- Star Wars: Jedi Knight: Dark Forces II
- Star Wars: Jedi Knight II: Jedi Outcast
- Star Wars: Jedi Knight: Jedi Academy
- Specter of the Past
- Specter of the Past unabridged audiobook
- The New Jedi Order: Enemy Lines II: Rebel Stand
- The New Jedi Order: Traitor
- Fate of the Jedi: Outcast (Mentioned only)
- Fate of the Jedi: Outcast audiobook (Mentioned only)
- Fate of the Jedi: Abyss
- Fate of the Jedi: Abyss audiobook
- Fate of the Jedi: Allies
- Fate of the Jedi: Allies audiobook
- Fate of the Jedi: Vortex
- Fate of the Jedi: Vortex audiobook
- Fate of the Jedi: Ascension
- Fate of the Jedi: Ascension audiobook
- Fate of the Jedi: Apocalypse
- Fate of the Jedi: Apocalypse audiobook
- Crucible audiobook
- Star Wars: The Roleplaying Game (Indirect mention only)
- Star Wars: Power of the Jedi
- Dark Empire endnotes
- Dark Empire Sourcebook
- The Movie Trilogy Sourcebook
- Wretched Hives of Scum & Villainy
- "Dangers from the Dark Side: Villains for the Star Wars: New Republic Campaign, Part Two"—Polyhedron 104
- The Dark Forces Saga
- Obi-Wan: Prima's Official Strategy Guide
- The Complete Star Wars Encyclopedia