Here is the full list of all 12 Alan Wake's American Nightmare achievements. It takes around 8-10 hours to unlock all of the achievements on Windows.
You have defeated 2,000 Taken.
You have unlocked all of the Nightmare Arcade Mode levels.
You got 70,000 points in a Nightmare Arcade level.
You survived an Arcade level using nothing but the flashlight and handheld flares.
You got a six-minute survivor streak and over 100,000 points in an Arcade level.
You got every manuscript page in the game.
You made it through the night and enjoyed a nice sunrise in one of the Arcade levels.
You used Mr. Scratch’s own trap to destroy him.
You took out two Splitter spawns with a single shot.
You secured the coolant tanks at the observatory.
You rewrote reality and brought down the satellite.
You reached the relative safety of the motel.