There are 51 Trophies that can be collected.

Bronze

Driven
Return to active duty.

Bringer of War
Chase down an assassin.

Mobilizer
Bring a veteran officer aboard.

World Shaker
Destroy an Atlas dropped from orbit.

Pathfinder
Explore a lost city.

Tunnel Rat
Survive the swarm.

Party Crasher
Sabotage a dreadnought.

Hard Target
Call down an orbital strike.

Saboteur
Disable a group of fighter squadrons.

Arbiter
Win a political stand-off.

Last Witness
Extract ancient technology.

Executioner
Defeat an old adversary.

Well Connected
Send a warning across the galaxy.

Fact Finder
Discover an enemy's monstrous origin.

Liberator
Stop a Cerberus kidnapping.

Problem Solver
Evacuate a scientific facility.

Patriot
Make the final assault.

Shopaholic
Visit a store in the single-player campaign.

Lost and Found
Dispatch 10 probes to retrieve people or resources in Reaper territory.

A Personal Touch
Modify a weapon.

Paramour
Establish or rekindle a romantic relationship.

Focused
Evolve any of your powers to rank 6.

Recruit
Kill 250 enemies.

Soldier
Kill 1,000 enemies.

Bruiser
Kill 100 enemies with melee attacks.

Untouchable
Escape a Reaper in the galaxy map.

Defender
Attain the highest level of readiness in each theater of war.

Overload Specialist
Overload the shields of 100 enemies.

Sky High
Lift 100 enemies off the ground with powers.

Pyromaniac
Set 100 enemies on fire with powers.

Eye of the Hurricane
Kill a brute while it's charging you.

Mail Slot
Kill 10 guardians with headshots from the front while their shields are raised.

Hijacker
Hijack an Atlas mech.

Giant Killer
Defeat a Harvester.

Enlisted
Start a character in multiplayer or customize a character in single-player.

Tour of Duty
Finish all multiplayer maps or all N7 missions in single-player.

Always Prepared
Obtain two non-customizable suits of armour.

Tourist
Complete one multiplayer match or two N7 missions.

Explorer
Complete three multiplayer matches or five N7 missions.

Almost There
Reach level 15 in multiplayer or level 50 in single-player.

Peak Condition
Reach level 20 in multiplayer or level 60 in single-player.

Battle-Scarred
Promote a multiplayer character to the Galaxy at War or import an ME3 character.

Silver

Legend
Mission accomplished.

Master and Commander
Deliver most of the Galaxy at War assets to the final conflict.

Long Service Medal
Complete Mass Effect 3 twice, or once with a Mass Effect 2 import.

Combined Arms
Perform any combination of 50 biotic combos or tech bursts.

Veteran
Kill 5,000 enemies.

Gunsmith
Upgrade any weapon to level 10.

Gold

Insanity
Finish the game on Insanity without changing difficulty after leaving Earth.

Unwavering
Finish all multiplayer maps on Gold or all single-player missions on Insanity.

Platinum

N7 Elite
Acquire all trophies.

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