Before playing Miranda's loyalty mission, wait for Jack's mission to become available and play it first. After the mission when they are fighting, support Jack. Miranda's loyalty will be low. After that, play her loyalty mission to get it back.

-Take Legion to the Citadel, then talk to Anderson and the customs officer.

-Take Legion to the migrate fleet on Tali's Loyalty mission. Security will force you to remove him unless you persuade them otherwise.

-Take Legoin to recruit Tali. She will attempt to shoot him.

The Citadel's game shop is a reference to a GameStop store.

To get the Pulse Rifle, switch to Hardcore difficulty setting before landing on the planet. Complete Tali'Zora's recruitment mission. The Geth Pulse Rifle will be in the room where you find Tali. Then, change the difficulty back to your original setting.

The Dominate skill, the Retrain Powers and Advanced Training upgrades, and plenty of Element Zero are required. You can get the Dominate Skill by recruiting Morinth (Samara's daughter), which means you must sacrifice Samara in her own loyalty mission. A list of planets with Element Zero can be found below. First, buy Advanced Training and choose Dominate. This will land you a bonus skill point, which you can use by instituting the Retrain Powers upgrade. Repeat as desired.

To find easy mining planets, go to the Micah system in the Vallhallan Threshold and find the three planets hidden in the asteroids. They are all "Rich" planets with a lot of materials that will help with upgrades.

While evolving a skill to level 4, press A + X to regain all spent squad points and keep the skill evolution. This works best if you level a skill from 0 to 4 (10 points) in one go.

Recruit Morinth to get the Dominate skill and get a decent amount of Element Zero. Buy the Advanced Training upgrade and choose Dominate. This result in a bonus skill point, which is then used by the Retrain Powers upgrade. Repeat as desired to continue gaining skill points.

Head to the Local Cluster and survey Uranus. Rather than the usual "Probe Launched", the voice will instead make comical jokes such as "Really Commander?" and "Probing Uranus".

Walk around the ship in between missions to hear some funny quotes:

-Stand near Jeff "Joker" Moreau (the pilot) without interacting with him. You will hear him say things such as the following:

"Why is it always claws and guns? Can't we piss off a fuzzy planet? Still dangerous, I know. But hey, bunnies."
"Two years and everything hits the crapper. That'll teach you to die on me."
"You know what I hate about deep space? Crap radio stations from two centuries back. My gosh, we were idiots."

-Stand next to the two engineers near the Mass Effect Core to hear the the following:
Engineer Daniels: "Did you know we're sharing our deck with a krogan?"
Engineer Donnelly: "Well that's just peachy."

There are three "Rich" mining planets with lots of materials. Go to the Micah system in the Vallhallan Threshold, and look for the three planets in the asteroids.
Move the pointer to the left or right of the planet you wish to scan. Press Left Analog-stick and Right Analog-stick in the same direction to double the spin speed of the planet and allow you to locate resources on the grid line quickly.

The following armor pieces will become available for purchase throughout the game:

Helmets
N7 Helmet - +5% health
N7 Breather Helmet - +5% health
Kuwashii Visor - +10% headshot damage; at Omega
Death Mask - +10% negotiation bonus; at Tuchanka
Umbra Visor - +5% power damage; requires linking Dr. Pepper bonus code to EA account
Recon Hood - +5% weapon damage; requires linking Dr. Pepper bonus code to EA account
Sentry Interface - +5% shield strength; requires linking Dr. Pepper bonus code to EA account

Shoulders
N7 Shoulder Guards - +3% weapon damage
Amplifier Plates - +5% power damage; at Illium
Strength Boost Pads - +25% melee damage; at Omega
Asymmetric Defense Layer - +5% health; at Tuchanka

Chest
N7 Chestplate - +5% power damage
Capacitor Chestplate - -10% shields regeneration delay; at Citadel, Illium, or Omega
Aegis Vest - +5% health; at Citadel
Shield Harness - +5% shields; at Tuchanka

Arms
N7 Gauntlets - +3% health
Heavy Damping Gauntlets - +5% shields ; at Tuchanka
Off-Hand Ammo Pack - +10% spare ammo capacity; at Citadel
Stabilization Gauntlets - +5% weapon damage; at Omega

Legs
N7 Greaves - +3% shield strength
Stimulator Conduits - +10% storm speed; at Omega
Life Support Webbing - +10% health; at Citadel
Ordinance Packs - +10% spare heavy weapon ammo; at Omega

Armor Sets
Blood Dragon Armor - +15% power damage, +10% shield strength; requires Dragon Age - Origins
Terminus Assault Armor - +10% storm speed, +15% shields, +1 weapons reserve ammo; requires pre-order bonus code
Inferno Armor - +10% negotiation bonus, +10% power damage, +10% storm speed by 10%; requires pre-order bonus code
Collector Armor - +10% regeneration, +10% storm speed, +20% health; requires Collector's Edition

This trick requires any Biotic that lifts your enemy off the ground and the Cryo Bomb tech. Use the Biotic to lift your enemy off the ground and hit him with the Cryo Bomb while he is still under the Biotic's effect. This will cause him to be stuck in a permanent falling state, where he is incapable of causing any damage. This is extremely useful when attempting to prevent the deployment of Harbinger, because once he enters the glitched body he cannot move. By doing this, you can kill him at the end of a fight to prevent him from jumping to another body.

Search the following planets to find Element Zero:

Eagle Nebula, Relic Cluster, Planet Preying Mouth
Eagle Nebula, Amun Cluster, Planet Anhur
Eagle Nebula, Amun Cluster, Planet Sekhmet
Crescent Nebula, Lusarn Cluster, Planet Tarith
Crescent Nebula, Zelene Cluster, Planet Helyme
Hourglass Nebula, Faryar Cluster, Planet Daratar
Hourglass Nebula, Osun Cluster, Planet Erinie
Hourglass Nebula, Ploitari Cluster, Planet Thegan
Rosetta Nebula, Alpha Draconis Cluster, Planet 2175 Aeia
Rosetta Nebula, Enoch Cluster, Planet Joab
Rosetta Nebula, Enoch Cluster, Planet Laban
Rosetta Nebula, Enoch Cluster, Planet Mizraim
Titan Nebula, Haskins Cluster, Planet Capek
Valhallan Threshhold, Micah Cluster, Planet Farlas
Valhallan Threshhold, Micah Cluster, Planet Israfil
Valhallan Threshhold, Micah Cluster, Planet Kakabel
The Shrike Abyssal, Urla Rast Cluster, Planet Talis Fia
The Shrike Abyssal, Xe Cha Cluster, Planet Tosal Nym
The Shrike Abyssal, Xe Cha Cluster, Planet Zada Ban
Sigurd's Cradle, Decoris Cluster, Planet Sanctum
Sigurd's Cradle, Skepsis Cluster, Planet Watson
Omega Nebula, Batalla Cluster, Planet Nearog
The Phoenix Massing, Salahiel Cluster, Planet Ekuna
Krogan DMZ, Nith Cluster, Planet Mantun
Minos Wasteland, Caestus Cluster, Planet Invictus
Nubian Expanse, Kalabsha Cluster, Planet Yamm
Far Rim, Dholen Cluster, Planet Gotha
Hades Nexus, Sheol Cluster, Planet Gei Hinnom
Hawking Eta, Schwarzschild Cluster, Planet Etamis
Caleston Rift, Aysur Cluster, Planet Arvuna
Caleston Rift, Balor Cluster, Planet Caleston

Fire the M-920 Cain and keep [Fire] held while pressing [Reload] after each shot to have the shots keep firing during the previous shots' explosions.

During the Freedom's Progress mission, when you are told to place your teammates around the giant blast door, you can trick the game into spawning extra YMIR Mechs. First, position your team accordingly and watch the cutscene. You'll now face a Giant YMIR Mech. Instead of killing it, turn around, and head BACK through the blast door. This will glitch the game back before the cutscene. Place your team around the blast door again, and the cutscene will play. This will spawn an extra YMIR Mech. Repeat as many times as desired, but more than three YMIR Mechs will most likely kill you.

Dominate is an excellent Biotic ability that allows you to control organic enemies and turn them into allies, similar to the Hack ability that controls synthetics. In order to get this ability as a Loyalty mission bonus to use for your character, help Morinth kill Samara during the latter's loyalty mission. However, if you want to keep Samara on your team but still have Morinth's Dominate ability, use the following trick. Play Samara's loyalty mission up to the point where Samara confronts Moritnth. Save the game right before the confrontation. When it is time to select who you will eliminate, choose the option that lets Morinth get the upper-hand on Samara and kill her. Create a separate saved game file. Go to the ship and talk to Morinth. Load the previous saved game then have Samara kill Morinth. You now get to keep Samara as a squad mate and have Morinth's Dominate ability when you choose a bonus loyalty power to add to your character in the prototype upgrade screen.

While recruiting Tali on Haestrom, direct sunlight will damage you and your squad's shields and Biotic barriers. Since Grunt uses armor, he is not harmed by the sunlight.

To unock the Dr. Pepper bonus items, go to http://www.drpepper.com/promotions/ea/signin/, and register for an account. You can register three different accounts to redeem three different codes and get each bonus item. Enter one of the following redemption codes, and select the "No Purchase" option:

CBEEAAA41NWH
CBEEAAAE4L9N
CBEEAAAFQG9J
CBEEAAAE98ZV

Choose the "Redeem" button to get a login for an EA account. Log in with your EA account information that is linked to Mass Effect 2. Select Mass Effect 2 from the game list, and select the desired bonus item. Repeat the steps with a new drpepper.com account to get the other bonus items.

Complete a party member's Loyalty mission to unlock alternate colors for their armor/clothing.

Approach Legion in his quarters, then highlight him but do not speak to him. He will eventually do the "Robot" dance.

Sometimes after you completea hacking minigame for credits etc. you can press A repeatedly as the window closes and cause the game to glitch out and let you hack a second time.

Scan the following planets to find anomalies:

Caleston Rift, Solveig Cluster, Planet Sinmara
Caleston Rift, Talava Cluster, Planet Taitus
Crescent Nebula, Lusarn Cluster, Planet Tarith
Crescent Nebula, Zelene Cluster, Planet Helyme
Eagle Nebula, Amun Cluster, Planet Neith
Eagle Nebula, Strabo Cluster, Planet Jarrahe Station
Hades Nexus, Sheol Cluster, Planet Gei Hin
HourGlass Nebula, Faryar Cluster, Planet Daratar
HourGlass Nebula, Ploitari Cluster, Planet Zanethu
Minos Wasteland, Fortis Cluster, Planet Aequitas
Omega Nebula, Ariniarkan Cluster, Planet MSV Strontium Mule
Omega Nebula, Fathar Cluster, Planet Lorek
Pylos Nebula, Dirada Cluster, Planet Canalus
Pylos Nebula, Nariph Cluster, Planet MSV Broken Arrow
Rosetta Nebula, Enoch Cluster, Planet Joab
The Shrike Nebula, Xe Cha Cluster, Planet Zada Ban
Sigurd's Cradle, Decoris Cluster, Planet Sanctum
Sigurd's Cradle, Skepsis Cluster, Planet Franklin
Titan Nebula, Haskins Cluster, Planet Capek

At the end of the game, examine the terminal that has all your teammates' dossiers. Read Legion's dossier to find out that he is a gamer. It will list the games that he has downloaded, his leaderboard scores, and other information about his gaming past.

When asking Zaal'Koris about his funny name/ship name the "Qwib Qwib" (on the Quarian fleet vessel), the real joke is when he mentions desiring a more respectable ship name like "Defrahnz" or "Iktomi." These two names would have resulted in the following Quarian names: Zaal'Koris vas Defrahnz (vas deferens) and Zaal'Koris vas Iktomi (vasectomy).

Take Legion to the Citadel. Talk to Anderson and the customs officer.

Take Legion to the migrate fleet on Tali's Loyalty mission. Security will force you to remove him unless you can persuade them otherwise.

Take Legoin to recruit Tali. She will try to shoot him.

Complete the game, then start a new game with the cleared saved game file to start with the following bonuses:

-Choose your Loyalty Bonus Skill from the start.
-Retain Skill Points but can redistribute them.
-Retain level and XP carry over; the max level is 30.
-+25% experience bonus for all characters
-Renegade/Paragon points are reset to neutral.
-Retain weapons and armor, but not the upgrades.

Notice after you press Y, the planet information screen on the right will tell you if the scan of planet reveals if it is "Rich", "Moderate", or "Poor". Rich planets typically give about 10+ good scan for ores. Ore yields vary from 1,500 to 3,000. Moderate will give about 8+ good scans, but around 35% to 55% yield compared to rich planets. Poor will give 5+ scans with yields 5% to 25% compared to rich planets. Note: If there is an anomaly on the planet (usually a rich planet) and you land before you scan, typically the Star Map on the Normandy will put you in a strange location away from the anomaly planet. Go back and rescan to get your ores.

Have a saved game file from the original Mass Effect on your hard drive, and use that profile in Mass Effect 2 to receive the following bonuses at the corresponding character levels:

BONUS - CHARACTER LEVEL
2,000 experience points - Level 50 Mass Effect character.
30,000 credits - Level 50 Mass Effect character.
5,000 of each resource - Level 50 Mass Effect character.
4,000 experience points - Level 60 Mass Effect character.
50,000 credits - Level 60 Mass Effect character.
10,000 of each resource - Level 60 Mass Effect character.

Unlock the following bonuses by completing the corresponding party member's Loyalty missions. You will also unlock their individuals skills for Shepard, alternate costumes, and increase the chance for surviving the suicide mission. Note: Complete the Advanced Training research upgrade for your ship to be able to select the skills:

BONUS - HOW TO UNLOCK
Biotic Barrier - Jacob's Loyalty mission.
Dominate - Kill Samara during her Loyalty mission and have Morinth replace her.
Fortification - Grunt's Loyalty mission.
Geth Shield Boost - Legion's Loyalty mission.
Inferno Grenade - Zaeed's Loyalty mission.
Neural Shock - Mordin Solus's Loyalty mission.
Reave - Samara's Loyalty mission.
Shield Drain - Tali's Loyalty Mission.
Slam - Miranda's Loyalty mission.
Warp Ammo - Jack's Loyalty mission.

To easily gain Paragon and Renegade points, you must first unlock training to be able to redistribute your skill points. Talent Mastery will add a certain percentage to your Paragon and Renegade points. Respec and distribute them into your Mastery repeatedly until your Paragon and Renegade are full.

Travel with Tali and Garrus, the party members back from Mass Effect. Eventually they will have a conversation about the elevators where Garrus remembers the interesting conservations they had about Quarrians. Tali gets very upset about to the point of threatening Garrus with her shotgun to stop.

If you chat it up with Yeoman Kelly Chambers often and choose to be kind to her you can instigate an "unusual" romantic encounter. You'll eventually be able to invite her to dinner. Additionally, you cannot let Kelly die in the final mission (choose a loyal escort for the crew in the final scene). After you beat the game, talk to Kelly and you'll receive an email from her. Go to your quarters and you'll be able to invite her up using your console. She'll appear and you'll be able to watch the evening's awkward events unwind. She's no Yeoman Rand, but she'll do.

Space Hamster is available on Illium. Once you enter your cabin and select him, he comes out and does the same "Squeek" that Boo did, who was Minsc's "Intergalactic Space Hamster" from Baldur's Gate and Baldur's Gate 2.

Note: This procedure requires editing a game file; creating a backup copy of the file before proceeding is recommended. With a text editor, edit the "Coalesced.ini" file in the "\Program Files\Team JPN\Mass Effect 2\BioGame\Config\PC\Cooked" directory. Change the indicated lines in the file to their new values to unlock the corresponding cheat:CHEAT FUNCTION/ORIGINAL LINE - MODIFIED LINE
No reloads     (AmmoPerShot=1) - AmmoPerShot=0
Unlimited ammo [NOTE 1] (bInfiniteAmmo=true) - bInfiniteAmmo=false
Extra health (Health=1500) - Health=9500
More Medigel (MaxMedigel=1) - MaxMedigel=9
More Probes (MaxProbes=30) - MaxProbes=90
More fuel (MaxFuel=1000) - MaxFuel=3000
NOTE 1: There are multiple instances of this line in the file.