Game Achievements:

• A Feeling Like Floating - Dissolve a turret. (5 Gamerpoints)
• Cupcake - Beat 5 advanced chambers (10 Gamerpoints)
• Fruitcake - Beat 10 advanced chambers (25 Gamerpoints)
• Go for the Gold - Win a gold metal on a challenge map. (15 Gamerpoints)
• Is Anyone There? - Complete the game without ever taking a bullet. (20 Gamerpoints)
• Like a Rat - Trap yourself in a test chamber so that GLaDOS has to help you continue. (20 Gamerpoints)
• Out of the Blue - Once you have control of both portals, only enter the orange portal. (25 Gamerpoints)
• Rat's Tale - Find all the Rat Man dens. (15 Gamerpoints)
• Saw That One Coming - Cause a rocket sentry to destroy its own rocket when the rocket has been redirected back towards it. (5 Gamerpoints)
• Tests Like Chicken - Find the chicken's test results. (15 Gamerpoints)
• The Camera Adds 10 Pounds - Knock a turret over with a security camera. (10 Gamerpoints)
• Vanilla Crazy Cake - Beat all advanced chambers (35 Gamerpoints)