Here is the full list of all 12 RAW Realms of Ancient War achievements.
Hit an enemy for 2500 HP damage
Finish the game with all heroes
Complete the game with any hero
Raise all of your skills to level 1
Find 5 statues of Kilthi
Complete 50 quests
Equip epic or legendary armor
Possess 15 mobs
Start a cooperative game
Collect 50,000 gold coins
Kill 1000 mobs in the campaign
Complete a level without dying