Here's a tip for those struggling on very hard on how to get the achievement :)
First you're going to want to play a normal game you can complete on any difficulty, but you want to first beat the game by taking over all zones on the map, then you are going to want to train up 5 characters, or as many as you want (though you only need and can use 5) to have high stats, 10 in all would be great however I did it with only level 10 attack and either building/leader, which are the core stats your going to need to improve.
Then you are going to want to win the game by drafting the constitution in the town hall, this will take you to the end of the game menu and by then clicking on continue you will be able to click on the town hall again, and chose to start a new game through this.
This will allow you to take 5 experienced characters through to an entirely new game, where you can play for the achievement
You are then going to want to play the game as you normally would
+ Is this helped :)
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