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