Complete the following achievements to unlock Xbox Live Gamerscore points.

Achievement	How to unlock
And It Continues ( 25 points )	Complete the single player campaign on Normal mode.
Backstory ( 25 points )	Complete the co-op campaign.
Father Forgive Me... ( 20 points )	Defeat the Priest.
Grindhouse ( 15 points )	Perform 100 chainsaw kills.
Just Getting Started ( 5 points )	Take out 20 enemies.
Just That Good ( 25 points )	Complete the single player campaign on Hard mode.
Make a Name For Yourself ( 10 points )	Take out 100 enemies.
Mow 'Em Down ( 15 points )	Take out 1000 enemies.
Revenge is Sweet ( 20 points )	Defeat Cesar.
Scars From the Past ( 15 points )	Defeat Cassandra.
The Meating ( 15 points )	Defeat the Butcher.
The Wrong Guy ( 10 points )	Defeat El Raton