Hyperions are a race of sentient suns. In order to stop their attempted conquest of the universe, their home planet, Hyperios, was destroyed by an alliance that included the Time Lords, Silurians, and Sontarans. A member of the race resurfaced on Isen VI and was able to take control of drones and terraforming machinery. The Twelfth Doctor and Clara Oswald helped defeat the individual Hyperion, but they appear be resurfacing on other planets.
- Read more about this topic on the Tardis Data Core.