Discords power is not his own...
A unicorn cast himself out for causing chaos that left its mark through the village. His passion was that of music, though a foal he was not that of average. He was intelligent, and his magical ability was immense though the intent of the usage was not what he wished to do with it. Chaotic energy flowed through the veins of the innocent pony, Discord sensed this, and sought him out.
Discord has no true power of his own, he is only able to cast spells and use petty magic. He poses no threat to the land of Equestria, so the royal kingdom paid him no mind.
This story is based in the time a few years after the Time of Snow. The village of Trottingham was just being established, when things started to go wrong.