Complete the following achievements to unlock Microsoft Gamerscore points.

Achievement	How to unlock	Points
Alternate ending	Get alternate ending.	100
Canon ending	Get canon ending.	100
Mission 1	Complete Mission 1 on any difficulty.	100
Mission 2	Complete Mission 2 on any difficulty.	100
Mission 3	Complete Mission 3 on any difficulty.	100
Mission 4	Complete Mission 4 on any difficulty.	100
Mission 5	Complete Mission 5 on any difficulty.	100
Mission 6	Complete Mission 6 on any difficulty.	100
Mission 7	Complete Mission 7 on any difficulty.	100
Mission 8	Complete Mission 8 on any difficulty.	100