“Sombra was the last king of the Crystal Empire and the reason for its banishment into the ice of the Frozen North for a thousand years.” Luna supplied. “He is a very dangerous foe. A unicorn who made himself near-immortal by corrupting his very essence with the darkest of magics. He enslaved the entire population of the Empire to do his bidding and waged war against most of his neighbors for nearly a decade before my sister and I defeated him.”