Stark (The Pandorica Opens)

Commander Stark was a Sontaran Commander. He and the rest of the Sontaran race were members of the Alliance, as were the Daleks, the Cybermen, the Autons, the Silurians and more of the Doctor's enemies. They planned to trap him in the Pandorica in 102, believing him the one causing cracks in the universe. (TV: The Pandorica Opens)

He was destroyed when the TARDIS exploded nonetheless. The Eleventh Doctor later prevented this, resulting in the Alliance never having been formed in the first place. (TV: The Big Bang)