Here is the full list of all 15 Keyboard Killers achievements. It takes around 2-3 hours to unlock all of the achievements on Windows.
666 KILLS
9999 KILLS
25000 KILLS
100000 KILLS
Click MainMenu
Click Undo
Click Backspace
Click Tutorial
Click Enter
Click End
Accuracy 100%
Kill 1111 meteors in 1 lvl
Click Pause
Change Music Vol
Quit the game