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.
Reached the ending.
Completed Great Seal - Part 2.
Completed Demander of Power.
Completed Primordial Dream - Part 2.
Acquired all rewards from training.
Completed all training battles.
Completed Kuuya.
Completed Mask.
Completed The Fallen.
Completed Burning Prison.
Used every main character's final strike.
Completed Abh-kamu.
Completed Hunter & Hunted - Part 2.
Completed Hansana Offense & Defense.
Completed The Daybreakers.
Dealt 1,800+ damage to a single enemy.
Used every main character's co-op chain.
Dealt 750+ damage to a single enemy.
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.
Tried training.
Completed Decisive Battle.
Completed Imperial Capital Invasion.
Dealt 300+ damage to a single enemy.
Completed Nuwangi.
Completed Tatokori Gate.
Completed Daughter of the Forest.
Used a co-op chain.
Used a final strike.
Completed Path of No Return.
Completed Revolt.
Completed Ruler of the Wild Forest.
Tried a free battle.
Completed Uninvited Guests.
Successfully performed a chain attack.