Complete the following achievements to unlock Microsoft Gamerscore points.

Achievement	How to unlock
Breaching the Tunnels (15 points)	Successfully defend the tunnel entrance.
Combat on the roof (15 points)	Survive the horde on the roof.
Defeat Harlow (15 points)	Defeat Harlow.
First Do No Harm (30 points)	Finish hospital quests for Cecil.
Heart of Darkness (15 points)	Find a boat for use in the jungle.
Henderson Town (15 points)	Reach Henderson.
Meeting Serpo (15 points)	Make pact with Serpo.
Military Base (30 points)	Gain access to a long-range radio station.
Serving Science (30 points)	Finish quests for Dr. Kessler.
The Cinema (15 points)	Clear out the cinema.
The Docks (15 points)	Enter the docks in Quarantine Zone.
The Storm (15 points)	Escape from the ship.
You've tricked me once (30 points)	Finish the game.