Full list of all 68 Mass Effect 3 achievements worth 1,550 gamerscore. It takes around 50-60 hours to unlock all of the achievements in the base game.
The base game contains 50 achievements worth 1,000 Gamerscore, and there are 4 DLC packs containing 18 achievements worth 550 Gamerscore.
Return to active duty.
Chase down an assassin.
Bring a veteran officer aboard.
Destroy an Atlas dropped from orbit.
Explore a lost city.
Survive the swarm.
Sabotage a dreadnought.
Call down an orbital strike.
Disable a group of fighter squadrons.
Win a political stand-off.
Extract ancient technology.
Defeat an old adversary.
Send a warning across the galaxy.
Discover an enemy's monstrous origin.
Stop a Cerberus kidnapping.
Evacuate a scientific facility.
Make the final assault.
Visit a store in the single-player campaign.
Deliver most of the Galaxy at War assets to the final conflict.
Dispatch 10 probes to retrieve people or resources in Reaper territory.
Complete Mass Effect 3 twice, or once with a Mass Effect 2 import.
Finish the game on Insanity without changing difficulty after leaving Earth.
Modify a weapon.
Establish or rekindle a romantic relationship.
Perform any combination of 50 biotic combos or tech bursts.
Evolve any of your powers to rank 6.
Kill 250 enemies.
Kill 1,000 enemies.
Kill 5,000 enemies.
Kill 100 enemies with melee attacks.
Escape a Reaper in the galaxy map.
Attain the highest level of readiness in each theater of war.
Overload the shields of 100 enemies.
Lift 100 enemies off the ground with powers.
Set 100 enemies on fire with powers.
Kill a brute while it's charging you.
Kill 10 guardians with headshots from the front while their shields are raised.
Hijack an Atlas mech.
Defeat a harvester.
Start a character in multiplayer or customize a character in single-player.
Finish all multiplayer maps or all N7 missions in single-player.
Obtain two non-customizable suits of armor.
Complete one multiplayer match or two N7 missions.
Complete three multiplayer matches or five N7 missions.
Upgrade any weapon to level 10.
Reach level 15 in multiplayer or level 50 in single-player.
Reach level 20 in multiplayer or level 60 in single-player.
Promote a multiplayer character to the Galaxy at War or import an ME3 character.
Finish all multiplayer maps on Gold or all single-player missions on Insanity.
Find all required intel to help Eden Prime's colonists.
Learn more about the Prothean Empire.
Investigate a sinister conspiracy.
Uncover an ancient secret.
Use clues to pinpoint the exact location of an objective.
Rescue a civilian from Reaper forces.
Free Omega from Cerberus Occupation.
Find the Talon leader.
Complete all the Command Center side-missions on Omega.
Discover a plot against you.
Go undercover to follow a lead.
Infiltrate an enemy stronghold with your crew.
Stop an out-of-control scheme before it's too late.
Throw a party for your friends.
Win a prize at one of the arcade games.
Investigate a strange occurrence in the combat simulator.
Score 9999 points in the combat simulator on Normal, Hardcore, or Insanity.
Defeat a group of Spectre-level opponents on Normal, Hardcore, or Insanity.