Accomplish the indicated achievement to get the corresponding number of Gamerscore points:

Good Score (5 points): Get 20,000 points.
Demolition Man (15 points): Kill two enemies with a single stick of dynamite in a single player game.
All Tools (5 points): Pick up a whip, a bat, a knife, a drum, a carton, a stick of dynamite, and a rock.
Third Base (20 points): Finish mission 3 holding a baseball bat.
No Swimming (10 points): Pass the bridge in mission 3 without falling in the water.
Untouchable (20 points): Complete mission 1 in a single player game without being hit.
Invade the Base (15 points): Reach mission 4 in a co-op game without continues.
No Mercy (15 points): Take out all the enemies before the final boss in a single player game.
Sneaky (20 points): Avoid the wall traps in mission 4.
Bare Hands (20 points): Complete a single player game without using any object.
Get the Girl (20 points): Beat the other player at the end of a co-op game.
Hero (35 points): Complete a single player game without continues.