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.
Defeat an old adversary.
Send a warning across the galaxy.
Make the final assault.
Mission accomplished.
Deliver most of the Galaxy at War assets to the final conflict.
Complete Mass Effect 3 twice, or once with a Mass Effect 2 import.
Kill 5,000 enemies.
Hijack an Atlas mech.
Finish all multiplayer maps or all N7 missions in single-player.
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 10 guardians with headshots from the front while their shields are raised.
Perform any combination of 50 biotic combos or tech bursts.
Extract ancient technology.
Kill 1,000 enemies.
Call down an orbital strike.
Disable a group of fighter squadrons.
Start a character in multiplayer or customize a character in single-player.
Complete three multiplayer matches or five N7 missions.
Reach level 15 in multiplayer or level 50 in single-player.
Sabotage a dreadnought.
Discover an enemy's monstrous origin.
Establish or rekindle a romantic relationship.
Evacuate a scientific facility.
Win a political stand-off.
Explore a lost city.
Defeat a harvester.
Complete one multiplayer match or two N7 missions.
Lift 100 enemies off the ground with powers.
Survive the swarm.
Destroy an Atlas dropped from orbit.
Stop a Cerberus kidnapping.
Kill 250 enemies.
Dispatch 10 probes to retrieve people or resources in Reaper territory.
Escape a Reaper in the galaxy map.
Evolve any of your powers to rank 6.
Obtain two non-customizable suits of armor.
Bring a veteran officer aboard.
Set 100 enemies on fire with powers.
Kill a brute while it's charging you.
Modify a weapon.
Visit a store in the single-player campaign.
Chase down an assassin.
Return to active duty.
Finish the game on Insanity without changing difficulty after leaving Earth.
Overload the shields of 100 enemies.
Upgrade any weapon to level 10.
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.
Uncover an ancient secret.
Rescue a civilian from Reaper forces.
Investigate a sinister conspiracy.
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.