Complete the following achievements to unlock Xbox Live Gamerscore points.

Achievement	How to unlock
Captain ( 25 points )	Destroy 10 missiles in 1 game Classic game in Normal difficulty.
Colonel ( 30 points )	Have three enemies in play at once Evolved game in Normal difficulty.
Commander ( 20 points )	Get a 5-frag killing spree Multiplayer game in Ranked match.
Corporal ( 10 points )	Score 100,000 Classic game in Normal difficulty.
Ensign ( 15 points )	Destroy 10 Saucers Evolved game in Normal difficulty.
General ( 30 points )	Score 1,000,000 Classic game in Normal difficulty.
Lieutenant ( 15 points )	Have 5 lives in hand Evolved game in Normal difficulty.
Major ( 25 points )	Win a game without dying Multiplayer game in Ranked match.
Maniac ( 10 points )	Score 50,000 Classic game in Throttle Monkey mode.
Private ( 5 points )	Destroy a Super Tank Classic game in Normal difficulty.
Sergeant ( 10 points )	Win a game Multiplayer game in Ranked match.
Specialist ( 5 points )	Destroy a Tank by piloting a Missile Multiplayer game in Ranked match.