Achievements (Steam)
Complete each achievement to receive the allotted gamerscore:
Missing in Action (5) - Save your crew from an overwhelming attack.
The Convict (10) - Successfully recruit the biotic Convict.
The Krogan (10) - Successfully recruit the krogan.
The Archangel (10) - Successfully recruit Archangel.
The Professor (10) - Successfully recruit the Professor.
The Quarian (10) - Successfully recruit the quarian.
The Justicar (10) - Successfully recruit the Justicar.
The Assassin (10) - Successfully recruit the Assassin.
Very Elusive (10) - Return to active duty.
Friend or Foe (10) - Obtain geth technology.
Colony Defense (25) - Defend a human colony from attack.
Battlemaster (10) - Gain the loyalty of the krogan.
Fade Away (10) - Gain the loyalty of Archangel.
The Cure (10) - Gain the loyalty of the Professor.
Treason (10) - Gain the loyalty of the quarian.
The Prodigal (10) - Gain the loyalty of the Cerberus Officer.
Ghost of the Father (10) - Gain the loyalty of the Cerberus Operative.
Catharsis (10) - Gain the loyalty of the biotic Convict.
Doppelganger (10) - Help the Justicar resolve her mission.
Cat's in the Cradle (10) - Gain the loyalty of the Assassin.
A House Divided (10) - Hack a geth collective.
Ghost Ship (25) - Complete the investigation of a derelict alien vessel.
Suicide Mission (50) - Use the Omega 4 Relay.
Mission Accomplished (125) - Save humanity throughout the galaxy from certain annihilation.
Against All Odds (15) - Survive suicide mission.
Insanity (75) - Complete the game on the "Insanity" difficulty level without changing the setting.
No One Left Behind (75) - Keep your team alive through the suicide mission.
Long Service Medal (75) - Complete Mass Effect 2 twice, or complete it once with a character imported from Mass Effect 1.
Paramour (50) - Successfully pursue a relationship with a teammate.
Head Hunter (10) - Perform 30 headshot kills with any weapon on humanoid targets.
Brawler (10) - Shoot and kill 20 enemies while they're knocked back by a punch.
Big Game Hunter (10) - Thresher Maw defeated.
Tactician (10) - Hit 20 different targets with multiple biotic powers to combine the effects.
Agent (50) - Complete 5 missions discovered by scanning unexplored worlds.
Prospector (5) - Retrieve mineral resources by scanning and probing a planet in the galaxy map.
Explorer (10) - Visit 100% of the planets in an unexplored cluster.
Power Gamer (10) - Reach Level 30 with one character.
Scholar (15) - Unlock 15 new Mass Effect 2 codex entries.
Technician (15) - Obtain 10 technology upgrades.
Master at Arms (15) - Kill enemies with 5 different heavy weapons during the game.
Merciless (10) - Make 20 enemies scream as they fall or are set on fire.
Overload Specialist (15) - Disrupt the shields of 25 enemies.
Warp Specialist (15) - Warp the barriers of 25 enemies.
Incineration Specialist (15) - Incinerate the armor of 25 enemies.
Operative (15) - Complete a mission discovered by scanning an unexplored world.
Weapon Specialist (15) - Fully upgrade a weapon.
Scientist (10) - Complete any research project in the Normandy's laboratory.
Fashionista (5) - Personalize your armor in your quarters on the Normandy.
Power Full (15) - Evolve any power.
Highly Trained (15) - View all advanced combat training videos at Shepard's private terminal.
Additionally, there is one Zaeed DLC Achievement:
Revenge! (15) - Gain the loyalty of the mercenary.
Unlock Alternate Color Schemes and Loyalty Skills
New Colors for Party Members - Complete a party member's loyalty mission.
Unlock Loyalty Skills - Complete the Loyalty missions for each of your party members to unlock their individuals skills.
Prequel Bonuses
Have a saved game file from the original Mass Effect and use that profile in Mass Effect 2 to get the following bonuses: experience points based on your previous level; resources for weapon and armor upgrades; and Paragon and Renegade Points (including a bonus if you have the maximum amount of either Paragon or Renegade points).