Here is the full list of all 79 Broken Lines achievements.
Introduce yourself to the locals
Release Fry from Prison
Experience Lieutenant Brooks final words
Unmask an enemy
Encounter the blocked mountain pass
Find a crate with explosives
Blow up the radio tower
Warn the civilians about the upcoming flooding
Find petroleum
Encounter the maskless enemies
Sacrifice a soldier to blow up the dam
Complete the level “Wreck”
Complete the level “Uncertainty”
Complete the level “Release”
Complete the level “Certainty”
Complete the level “Clarity”
Complete the level “Revenge”
Complete the level “Survival”
Complete the level “Decency”
Complete the level “Cruelty”
Complete the level “Greed”
Complete the level “Strength”
Complete the level “Mischief”
Complete the level “Evasion”
Complete the level “Contact”
Complete the level “Power”
Complete the level “Recoil”
Complete the level “Spirit”
Complete the level “Worry”
Complete the level “Ambush”
Complete the level “Retribution”
Complete the level “Consequence”
Complete all levels in the entire game over several playthroughs
Complete Contact level in less than 4 minutes and 4 seconds
Complete Retribution level in less than 4 minutes and 12 seconds
Restart a level
Lose a campaign
End the campaign and blow up the dam
End the campaign and get successfully extracted by a plane
End the campaign and drive away over the mountains
End the campaign and walk home over the mountains
End the campaign and get surrounded and killed by vengeful enemies
End the campaign and get surrounded and killed by angry civilians
Experience all possible endings in the game
Conner rejects Avery’s advances
Wood and Hailey find the dog
Avery finds out about Wood’s fling
Conner and Hailey talk about her scar
King and Sherman have a confrontation
Fry and Hailey start fighting
Morgan opens up to Conner
Eat Izkor’s stew
Buy a weapon from Izkor
Buy the best shotgun: Browning Automatic 5
Buy the best rifle: Mosin-Nagant Scoped Rifle
Buy the best submachine gun: Sturmgewehr
Buy the fake grenade
Complete the campaign and never buy anything from Izkor’s shop
Kill 101 enemies
Cause 10 civilian casualties
Kill an enemy officer
Destroy a tank
Have a soldier desert your squad
Complete the campaign with 4 dead soldiers
Own 0 supplies and 0 salvage
Own more than 100 salvage
Find more than 10 supply crates in various levels during the same campaign
Kill three enemies with one grenade
Kill 5 or more enemy soldiers in a single turn
Have all your soldiers panic at the same time
Gain a gold medal from a mission
Equip a soldier with 3 abilities, 3 traits, and all equipment slots
Get your squad killed in Ambush!
Kill all enemies in the ambush in the level Ambush!
Fail a boot camp level
Complete all boot camp levels
Unlock a second Trait on a Soldier
Use Suppression 100 times
Kill an enemy after knocking them down 3 times