Here is the full list of all 38 Souldiers achievements.
Finish a game on Game+ mode.
Complete the game as all three classes.
Complete the game as a Caster.
Unlock all skills.
Destroy 10,000 environmental objects.
Complete the game as an Archer.
Defeat 5,000 enemies.
Upgrade your weapon to the highest level.
Reveal 100% of every map.
Collect all secondary weapons.
Find all of the hidden rooms.
Complete the Bestiary in your Encyclopaedia.
Collect all Dark Crystals.
Complete all side quests.
Upgrade your protection the highest level.
Defeat 50 enemies using secondary weapons.
Complete the game on Warrior mode.
Complete the game as a Scout.
Defeat Beigon on Soldier or Warrior mode.
Defeat Agginox on Soldier or Warrior mode.
Defeat all Dark Warriors.
Defeat Galath a second time.
Defeat Ratatosk on Soldier or Warrior mode.
Collect all orbs in the game.
Defeat Project S on Soldier or Warrior mode.
Destroy 3,000 environmental objects.
Discover 50 hidden rooms.
Defeat Sangrigor.
Defeat Brigard.
Defeat Birk on Soldier or Warrior mode.
Use 100 potions.
Defeat Babylon on Soldier or Warrior mode.
Inflict altered states on your enemies 50 times.
Defeat all Royal Scorpions.
Defeat 1,000 enemies.
Defeat Iktala on Soldier or Warrior mode.
Defeat the Minotaur
Be revived by the Valkyries after falling in combat.