Here is the full list of all 45 Of Orcs And Men achievements. It takes around 12-15 hours to unlock all of the achievements on Windows.
Answer Sork's provocation in a language he understands
Trade an item
Upgrade a Skill
Have Styx calm things down a bit
Poison three different enemies at the same time
Equip a full set of upgraded equipment (weapons and armor)
Bind Skills to both of each character's shortcut keys
Deal with the Scourge issue in the shantytown
Save a brunette in distress
Kill Dorek the Trainer
Put an end to the madness of the Shaman of the Bowels
Win the Black Hand challenge
Complete Chapter 1 on any difficulty setting
Survive the Row
Prevent a miners' revolt in the Mire
Let Styx take out the Imperial sentinels of the Mire on his own
Kill Gorkash the Head Foreman without further ado
Kill all the dug-in foremen and guards
Spare Dakath the repentant
Take pure water to the Shaman of the Mire
Be buddy-buddy with a force of nature
Confront Braggart with his lies
Put together a special squad to assault the Pillar
Finish Chapter 2 at any difficulty level
Kill the Imperial officer in the Monastery
Follow the path of the Assassin
Follow the way of the Shadowgoblin
Follow the path of the Berserker
Follow the path of the Master
Finish Chapter 3 at any difficulty level
Kill Emperor Damocles
Finish Chapter 4 at any difficulty level
Finish Chapter 5 at any difficulty level
Finish Of Orcs and Men at Easy level
Finish Of Orcs and Men at Normal level
Finish Of Orcs and Men at Hard level
Finish Of Orcs and Men at the highest difficulty level
Defeat a boss without using an automatic attack (assassinations excluded)
Learn every Skill in a single tree.
Learn and improve every Skill in a single tree.
Assassinate 47 enemies
Break 15 spinal columns while Berserk
Find and empty 20 chests
Hit eight enemies with a single attack
Put together the best squad possible to assault the Pillar