Full list of all 13 Heroes of Might Magic III - HD Edition achievements. It takes around 35-40 hours to unlock all of the achievements on Windows.
Use a cheat code
Complete the campaign "Spoils of War" on Krewlod's side
Complete the campaign "Seeds of Discontent"
Complete the campaign "Songs of the Father"
Complete the campaign "Liberation"
Complete the campaign "Long Live the King"
Complete 10 maps on Normal Difficulty without cheating
Complete 10 maps on Hard Difficulty without cheating
Complete 10 maps on Expert Difficulty without cheating
Complete 10 maps on Impossible Difficulty without cheating
Complete the campaign "Dungeons and Devils"
Complete the campaign "Spoils of War" on Tatalia's side
Complete the campaign "Long Live the Queen"