Prequel bonuses
Have a saved game file from the original Mass Effect on your hard drive, 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).

Completion bonuses
Successfully complete the game. Then, start a new game with the cleared saved game file to start with the following bonuses: choose Loyalty Bonus Skill at the start; retain Skill Points from first playthrough; retain level and experience points from first playthrough; Renegade/Paragon points reset to neutral; and your weapons and armor (but no upgrades) from first playthrough.

Quicker mining

While scanning a planet, do not hold LT. Instead, rapidly tap LT until you see a blip on the scanner. Then, go back over the area while holding LT to find the best location to send the probe.

Extra Paragon and Renegade points
During conversations, look carefully for a prompt at the top left area of the screen. Quickly press LT when the wings appear for extra Paragon points. Quickly press RT when the star appears for extra Renegade points.

Amusing surveying responses
Go to the Local Cluster, and survey Uranus. Instead of the usual "Probe Launched" response, the voice will instead make Uranus jokes such as "Probing Uranus" or "Really Commander?"

Achievements
Accomplish the indicated achievement to get the corresponding number of Gamerscore points:

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

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