I began last week this method found on true achievements.
I'm just doing angain ang again the 1st level of hatchery. I gain an average of 35-40 corns by run (I don't play, I just let the chicken fall) and I just have to touch the "replay" button.
I do it at work so it's not too much boring. I don't play at home.
I'm maybe at 300 000 corns collected by now.
I win an average of 4000 corns by hour and I work 35 hours/week so 1 week = an average of 140 000 corns !
If you begin from 0, It will take 7 weeks to do this achievement... Yeah it's very long !
Good luck to all the people who want this achievement ! You'll need it and see you next time to tell you my progress !