Here is the full list of all 38 Garrison: Archangel achievements.
Play a Mission for the very first time.
Get the Neutral Ending in Missions Mode.
Get the Bad Ending in Missions Mode.
Get the Imperial Legion Ending.
Get the Piedrana Separatist ending.
Get the Du Couronne ending.
Get the Sunfield Frontier ending.
Get the highest prestige rating for the Archangel Tournament League.
Get the highest prestige rating for the Pagetti Family.
Get the highest prestige rating for Eagle Aerospace.
Get the highest prestige rating for Montaglione.
Get the highest prestige rating for Medvedev.
Get the highest prestige rating for Stahlwalder-Nibelungenwerke.
Get the highest prestige rating for Shenji Manufacturing.
Get the highest prestige rating for Astra Solutions.
Get the highest prestige rating for Yoshikawa.
Get the highest prestige rating for Bleeding Edge.
Get the highest prestige rating for Maaga Industries.
Upgrade a weapon for the first time.
Reach maximum CERT.
Create an Archangel in the garage and name it for the first time.
Win a battle with the Dominus equipped.
Play Arcade Mode for the first time.
Finish Arcade Mode at least once in any difficulty.
Finish Arcade Mode in Insane Difficulty.
Clear arcade mode using an Archangel with no weapons equipped.
Play Horde Mode for the first time.
Clear Horde Mode.
Play Survival Mode for the first time.
Defeat at least 10 enemies in Survival Mode.
Play a custom game for the first time.
Unlock all the Arena Jockeys
Unlock all the Mission Ghosts.
Unlock all Music Tracks.
Unlock all Cutscenes.
Achieve Level 2.
Achieve Level 5.
Achieve Level 10.