Here is the full list of all 12 War Mines: WW1 achievements.
Complete the 1st stage.
Complete the 2nd stage.
Complete the 3rd stage.
Complete the 4th stage.
Complete the 5th stage.
Complete the 6th stage.
Complete the 7th stage.
Complete the 8th stage.
Complete the 9th stage.
Complete any stage without marking any mine
Complete the entire game in less than 60 minutes.
Complete any stage without using the hint.