it was time when King Sombra was the ruler. The worst time of the whole Crystal Empire

Right now, you were lead along with other ponies with a chain on your neck to a factory to do robes for King Sombra. Then, with a corner of your eye, you saw your older brother who had the iron mask on his head, turned into his King Sombra's guard. It was heartbreaking as you stopped to look at him, but then other guard pushed you, so you will finally move and enter the factory