Although he may or may not have been expressly forbidden to, Star Swirl the Bearded (who had not quite grown into his facial hair at the time) has on occasion peered into the future. He beheld the return of Nightmare Moon, of Discord, of Sombra, and worst of all, to him, he beheld the loneliness of his immortal Tutor and Master, Celestia.

Then, he saw a way to fix it all.

...so long as he doesn't get caught.