Dawnbringer appears as a silver and gold gilded long sword hilt with a red star gem embedded into the pommel. It's blade, when present, is a shining blade of pure sunlight.
Dawnbringer was forged in the early days after creation, by Eladrin smiths dedicated to Shade. It fought in many wars, slaying the foes of Shade followers. Prior to the Eladrin Diverge, Dawnbringer was lost, no one knows where it was taken, or who had taken it. It was found, a significant time later, in Had'yss, in the tomb of some forgotten early high elf.
The one who found Dawnbringer desired to use the sword for great evil, and twisted the blade, infusing it with even more magic. At a certain point, the blade shattered, being able to contain no more the massive magical charge that was being put into it, and that energy remained, flowing from the swords hilt as a blade of pure sunlight. A side effect of this magical charge, was that the sword became sentient, and could sense its original purpose, a weapon forged for the use of those worshiping the gods, and in sensing this, it refused to be used for evil by its new wielder.
The wielder however, had other plans, and used his overwhelming willpower to dominate the blade, twisting it to his purpose, though it continues to resist when it can.