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