Full list of all 88 Titanfall achievements worth 2,000 gamerscore. It takes around 150-200 hours to unlock all of the achievements in the base game on Xbox One.
The base game contains 35 achievements worth 1,000 Gamerscore, and there are 4 DLC packs containing 53 achievements worth 1,000 Gamerscore.
Reached the highest Pilot generation
Won 50 Pilot Hunter matches
Earned 500 burn cards
Played every gameplay mode on every map
Won 50 Attrition matches
Won 50 Hardpoint matches
Won 50 Capture The Flag matches
Won 50 Last Titan Standing matches
Wallran for 5 kilometers
Won every Campaign level as a Militia pilot
Became a second generation Pilot
Played 50 Campaign matches
Unlocked everything
Won every Campaign level as an IMC pilot
Reached level 50
Completed the IMC campaign
Killed 10 ejecting Pilots
Killed 1000 AI soldiers
Completed all challenges for a single weapon
Killed an ejecting Pilot with the Plasma Railgun
Hacked 20 Spectres using the Data Knife
Snapped the necks of 10 Pilots
Called in your Titan 25 times
Reached level 25
Killed 5 enemies with one Arc Cannon shot
Killed 5 enemies by dropping a titan on them
Killed all pilots during the evacuation single-handedly
Completed the Militia campaign
Created a custom titan loadout
Caught a projectile shot from a vortex with your own vortex
Created a custom pilot loadout
Finished as the top player on your team once
Survived an evacuation
Rodeo-killed a Titan
Completed training
Played every game mode on Runoff
Killed 100 Pilots on War Games
Played every game mode on War Games
Played every game mode on Swampland
Killed 12 Pilots in a single match on War Games
Won a match on Swampland
Killed 200 enemies on Runoff
Killed 25 enemies while wall running on Runoff
Won a match on Runoff
Didn't touch the ground for 60 seconds on Swampland
Won a match on War Games
Was airborne for 500 Meters on Swampland
Killed 15 titans while you had a Titan Burncard active on Haven
Played every game mode on Haven
Played every game mode on Export
Played every game mode on Dig Site
Killed 50 Pilots on Dig Site
Won a match on Export
Killed 12 pilots in a single match on Dig Site
Executed 2 titans in a single match on Haven
Killed an enemy with the trap on Export
Killed 25 enemies while cloaked on Export
Won a match on Haven
Won a match on Dig Site
Played every game mode on Backwater
Played every game mode on Sand Trap
Played every game mode on Zone 18
Killed 10 Pilots as a Titan in a single match on Zone 18
Killed 10 Pilots while stim was active on Zone 18
Killed 10 Pilots while Active Radar Pulse was active on Sandtrap
Killed an enemy with AMPed vortex shield deflection on Backwater
Melee killed 15 enemies while cloaked on Backwater
Won a match on Zone 18
Killed 2 Titans as a Pilot in a single match on Sandtrap
Won a match on Sand Trap
Won a match on Backwater
Completed 100 Daily Challenges
Earned Gen 10 without using a Forged Certification on a regen challenge
Earned 500,000 Black Market Credits
Purchased 100 items from the Black Market
Earned 50 Battlemarks in Ranked Play
Played a ranked match
Purchased all Titan OS Voice Packs
Earned at least 2 stars on 15 different maps in Frontier Defense
Earned a total of 50 Stars
Got a 10 game winstreak
Unlocked 50 Titan Insignias
Used 5 Titan Burncards
Earned 3 stars for a single map and mode
Got a 5 game winstreak
Discarded 100 Burncards in exchange for Black Market Credits
Completed all Daily Challenges for a day
Renamed a custom loadout