As you trot into Canterlot Castle, you see the usurper, King Sombra, and sitting beside him is Princess Celestia on the right, and Princess Luna on the left, both fully and utterly brainwashed by Sombra.

King Sombra: "Tsk, another pony not worth my time. My dears, tend to him why don't you, if he tried anything, kill him."

Princess Celestia: "As you wish, my king~."

Princess Luna: "At once, my king~."