Dr. Fetus' Mean Meat Machine

To unlock this achievement, you'll need to chain blocks six times in an unbroken combo. You're unlikely to get this just playing through the game normally since you need to setup a large number of blocks (far beyond most level requirements). Load up 2-1, activate God mode so the ghost doesn't interfere and copy my pattern below. Once you're setup, sit back and watch 'em fall! It's super satisfying : )