A dark energy trap was a dark side Force power, conjured through Sith magic by a Sith sorcerer. Dark energy traps resulted from intense concentrations of dark-side power. To a trained eye, they appeared as faint shimmers of purple in the air and, under the Sith practitioner's spell, could immobilize even a skilled Force-sensitive being for a time. They could, on the other hand, entrap indeterminately in duration a being who was unskilled.