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