Here is the full list of all 55 The Banner Saga 2 achievements.
Survive all battles on Easy.
Survive with only human Heroes. (Normal or Hard Difficulty)
Survive with only female Heroes. (Normal or Hard Difficulty)
Survive all battles on Hard.
Survive Hard Mode without a single reload
Complete the game on Normal difficulty.
Survive using only parties of 4 varl in every battle. (Normal or Hard Difficulty)
Survive with fewer than 20 Heroes dying. (Normal or Hard Difficulty)
Survive without a single Hero dying. (Normal or Hard Difficulty)
Survive without using the Horn for willpower. (Normal or Hard Difficulty)
Survive without Recruiting Heroes. (Normal or Hard Difficulty)
Survive all battles on Normal.
Survive in less than 180 minutes for your total turns. (Normal or Hard Difficulty)
Complete the game on Hard difficulty level without losing a single battle.
Reach Arberrang in 100 days or less.
Meet King Meinolf with Alette.
Prevail with Rook against overwhelming numbers.
Complete the game without letting anyone in your caravan die to hunger.
Complete the game without ever getting low morale.
Complete the game on Hard difficulty.
Meet King Meinolf with Rook.
Bring 400 clansmen safely into Arberrang.
Visit the godstone Lauga.
Fight 32 battles in a single playthrough.
Defeat 3 enemies with War Bear.
Maintain an alliance with Rugga.
Kill a Sundr.
Witness Eyeless possess 10 fallen units.
Bolverk always acts as the Ravens expect.
Reach Oldford with at least 20 Varl following Bolverk.
Break 30 barricades in a single playthrough.
Defeat 3 enemies with a Slaughterer.
Defeat 3 enemies with Zefr.
Kill 5 in one turn with Cull the Weak.
Complete Holfi's Training.
Visit the godstone Bygglaerer.
Acquire 3 rank 10 items.
Visit the godstone Geirraðr.
Complete Sven's Training.
Defeat 3 enemies with a Female Horseborn Cantref.
Defeat 3 enemies with a Male Horseborn Teulu.
Build an army of over 600 trained fighters.
Kill 5 enemies while stealthed.
Defeat 3 enemies with a Tracker.
Visit the godstone Vez'nan.
Visit the godstone Baldringr.
With 6 Rank 10 units, win a Hard difficulty sparring battle in the Training Tent.
Defeat 3 enemies with an Axe Thrower.
Visit the godstone Irynx.
Defeat 3 enemies with a Berserk.
Defeat 3 enemies with a Shieldmaiden.
Defeat 3 enemies with a Wanderer.
Import Save Game from Banner Saga 1.
Visit the godstone Aselei.
Defeat 3 enemies with a Poet.