Complete the following tasks to unlock Apple Game Center achievements.

Achievement	How to unlock
Annihilator (100 points)	Survive 40 days in Survival Mode.
Contract Assassin (100 points)	Complete Mission 10.
Contract Killer (50 points)	Complete Mission 5.
Due Diligence (50 points)	Complete the Tutorial.
Enforcer (60 points)	Survive 30 days in Survival Mode.
Guardian Angel (30 points)	Survive 20 days in Survival Mode.
Protector (20 points)	Survive 10 days in Survival Mode.
Rookie Of The Day (10 points)	Survive 5 days in Survival Mode.