XCOM: Enemy Unknown is out next week, and those who pre-ordered the game on Steam can now pre-load the game to save some time come launch. Those who pre-ordered through Green Man Gaming should check their inboxes for the key so they can start the pre-load process as well. The download size is approximately 12.3GB, according to Evil Avatar. XCOM: Enemy Unknown launches in North American on PC, PS3, and Xbox 360 on October 9 and in Europe on October 12. Watch the launch trailer here.