Steven Ter Heide was an employee of Guerilla Games. He joined Guerilla in 2005[1], and would go on to be the producer of Killzone: Liberation[2] and Killzone 2[2], the senior producer of Killzone 3[2], and the game director of Killzone: Shadow Fall[2].
On July 6th, 2017, he announced his departure from Guerilla Games on Twitter[3]