Miraak, the First Dragonborn

When Miraak, the First Dragonborn enters the battlefield, gain control of target Dragon creature
an opponent controls until Miraak leaves the battlefield.

"He was Dragonborn, yet he served the dragons. A
priest in their order, highly esteemed and very powerful.
Then he turned against them, becoming something they
feared."
-Storn Crag-Strider