Sontaran

A clone race, the Sontarans are humanoids with large, bulbous heads and stocky bodies. Their hands have two fingers and a thumb.

The Sontarans have achieved crude time-travel technology which is effective though not on par with the Time Lords.

The Sontarans are engaged in a destructive war with the Rutans, a race of jellyfish-like aliens capable of storing and discharging enormous amounts of electricity, and changing their appearance to appear humanoid.

The Sontarans have appeared in the following Dr. Who episodes: The Time Warrior The Sontaran Experiment The Invasion Of Time The Two Doctors