Here is the full list of all 20 Blades of the Righteous achievements.
Completed The Game on 'Easy' difficulty
Completed the game on 'Medium' difficulty
Completed the game on 'Hard' difficulty
Won 50 Battles
Won 100 Battles
Won 200 Battles
Won 500 Battles
First Battle Fought
Lost 10 Battles
Lost 25 Battles
Lost 50 Battles
Unlocked 'Orc' unit at the Talent Tree
Unlocked 'Orc Archer' unit in Talent Tree
Unlocked 'Barbarian' unit in Talent Tree
Unlocked 'Paladin' unit in Talent Tree
Unlocked 'Archer' unit in Talent Tree
Unlocked 'Angel' unit in Talent Tree
Unlocked 'Viking' unit in Talent Tree
Unlocked 'Spartan' unit in Talent Tree
Unlocked 'Samurai' unit in Talent Tree