On this map, you can quickly and easily complete the following achievements:
*You're a Monster!
*You Really Are a Monster!
*No… Really… You Are a Monster!
*The Conqueror
*Bear Grilled
*Make it Through the Winter
*Still Need More?
*The Barmy Armory
*Smaug

Set the maximum difficulty
Just point the archers in the direction of the road sign and throw cows.
It may take about half an hour to kill 1,000,000 units.
(Bears are waiting in the walls.)