Bird Launcher Achievement
Launch 5000 birds
This will most definitely come before you destroy 500k blocks, but if you wish to get this out of the way earlier, load up Level 4-30. This level has 7 birds to launch, the most in the game. Launch all the birds in rapid succession. As soon as your last bird leaves the slingshot, pause and restart the level and repeat the process until the achievement unlocks. This method will take around 2-3 hours to launch all 5000 birds.