Here is the full list of all 49 Utawarerumono: Prelude to the Fallen achievements.
Obtained all achievements.
Listened to every BGM.
Viewed all event scenes.
Completed Where the Wild Things March.
Completely filled out the encyclopedia.
Acquired all rewards from training.
Reached the ending.
Completed Great Seal - Part 2.
Completed Demander of Power.
Completed Primordial Dream - Part 2.
Completed all training battles.
Completed Kuuya.
Completed Mask.
Used every main character's final strike.
Completed The Fallen.
Used every main character's co-op chain.
Completed Burning Prison.
Completed Abh-kamu.
Dealt 1,800+ damage to a single enemy.
Completed Hunter & Hunted - Part 2.
Completed Hansana Offense & Defense.
Completed The Daybreakers.
Dealt 750+ damage to a single enemy.
Tried a free battle.
Completed Abandoned Feelings.
Completed Princess of a Fallen Empire.
Completed Pursuit.
Completed Karulawaturei.
Completed Infiltration.
Completed Giriyaginan Gladiator.
Completed False Truths - Part 2.
Completed Battle to the Death on the Bridge.
Completed Evenkurugan Woman.
Completed Special Attack.
Completed Blocking the Shikeripechim Invasion.
Dealt 300+ damage to a single enemy.
Tried training.
Completed Decisive Battle.
Completed Imperial Capital Invasion.
Completed Nuwangi.
Used a final strike.
Completed Tatokori Gate.
Completed Daughter of the Forest.
Used a co-op chain.
Completed Path of No Return.
Completed Revolt.
Completed Ruler of the Wild Forest.
Completed Uninvited Guests.
Successfully performed a chain attack.