Here is the full list of all 19 Symphony of War: The Nephilim Saga achievements.
Defeat all enemies in Chapter 12.
Complete the main story on Captain difficulty.
Complete the main story on Warlord difficulty.
Surrender all the Imperial Squads in Chapter 27.
Unlock all Techs in a single playthrough.
Reach Max Faction Rank.
Army size reaches 150 Units.
Have 9 Units in one Squad.
Surrender 200 enemy Units in a single playthrough.
Form a Bond relationship.
Rescue all 4 children in Chapter 15.
Reach Faction Rank 9.
Use a Proof of Merit on a Unit.
Defeat Beatrix in Chapter 11.
Hire a Unique Mercenary.
Class change to Tier 3.
Class change to Tier 2.
Find or purchase an Artifact of Legendary rarity.
Reach Faction Rank 4.