Phantom energy

Phantom energy was a state of dark energy. When the Starkiller Base superweapon released the quintessence it had collected within its core, it was transformed into phantom energy, which would follow the line of egress that had been provided by the weapon's technicians according to planetary rotation, inclination, etc, through a hole in "sub-hyperspace," until it was intercepted by an object of sufficient mass. When the beam of phantom energy interacted with a planet, it ignited its core, creating a pocket nova. Large amounts of phantom energy could create temporary rips in sub-hyperspace, which allowed the Hosnian Cataclysm in 34 ABY to become visible from across the galaxy as it happened.

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