Here is the full list of all 38 MORDHAU achievements.
Kill 20 enemies with the ballista
Land 10 headshots on enemies with projectiles in a single game
Kill 5 enemies with rocks
Kill 10 enemies in a row without dying
Battlecry 500 times
Kill 5 enemies with the mallet
Perform 20 disarms
Take 400 damage without dying
Finish off 10 enemies with a kick
Kill 20 enemies with the longsword
Regenerate to full health after getting down to 1 health
Kill 5 enemies with the lute
Block 1000 melee attacks
Kill 30 enemies with fists
Kill 10 enemies with fire
Kill 5 enemies by trampling them with the horse
Kill an enemy while you are on fire
Kill two enemies with a single attack from a melee weapon
Deflect a projectile with a strike
Take a melee weapon out of a living enemy’s body
Lose your head three times in a single match
Kill an enemy after dying
Complete the tutorial
Kill an enemy with an icicle
Kill 5 enemies with the bear trap
Kill an enemy with the training sword
Kill an enemy with the pommel throw
Kill 10 enemies with the carving knife
Kill 5 enemies with headshots with a couched weapon on horseback
Block 100 projectiles
Chamber 200 attacks
Decapitate 5 enemies in a single game
Kill 5 enemies while climbing a ladder
Get 30 assists in a single match
Get 30 kills in a single match
Cause someone to fall to their death after kicking them
Kill 1000 enemies
Reach 1000 assists