The Severance

Voragos was initially a continent on a larger planet, ruled by an authoritarian council of wizards. They desired absolute border control and to create their own paradise, and decided to turn their continent into their own planet. After a century of spellcrafting and constructing arcane landmarks they unleashed their spell, the Severance. The continent disappeared, space folded on itself, and it became its own small planet.
But things went wrong. The wizards had intended to merely separate their borders and stay in their solar system, but the power of the Severance was more than their anticipated. Nearly all the wizards were annihilated by the backlash, the land warped by newly untethered elemental forces, and the infant planet rocketed off into the depths of space without a sun!
The tiny planet was not doomed, however. A solar sacrificed itself to create a new, smaller sun. A circle of dwarven druids jury-rigged the elemental dynamos to stabilize the planet, and a popuar uprising deposed the last of the wizards (supposedly).