General Staal, also known as 'Staal the Undefeated', was commander of the Tenth Sontaran Battle fleet. Staal, his subordinate Skorr and their army of troopers invaded earth in 2009, planning to turn the planet into a cloning hub.

Staal’s personality was that of a typical Sontaran: a love of warfare, no respect for other races and a refusal to back down to his enemies at any cost. This stubborn refusal to surrender would eventually lead to his downfall.