Full list of all 82 Gears of War 3 achievements worth 2,000 gamerscore. It takes around 1000 hours to unlock all of the achievements in the base game.
The base game contains 50 achievements worth 1,000 Gamerscore, and there are 7 DLC packs containing 32 achievements worth 1,000 Gamerscore.
Earned the Onyx "War Supporter" medal.
Reached level 50.
Earned the Silver "Number 1" medal.
Recovered all 15 COG Tags.
Recovered all 42 Collectibles.
Earned an Onyx medal.
Completed all campaign Acts on Insane Difficulty.
Complete all Acts in 4 player Co-op on any difficulty.
Complete all Acts in Co-op on any difficulty.
Earned the Bronze "Force Multiplier" medal.
Earned the Bronze "Loot Courtesan" medal.
Executed your enemies with variety and style.
Wreaked vengence upon humanity!
Completed 5 Arcade Campaign chapters in co-op.
Reached level 25.
Survived all 50 waves of Horde.
Survived the first 10 waves of Horde.
Completed all campaign Acts on Casual or Normal Difficulty.
Completed all campaign Acts on Hardcore Difficulty.
Killed Myrrah.
Rescued Adam Fenix from captivity.
Turned off the Maelstrom device.
Passed under the Maelstrom and found Azura.
Launched the sub.
Found enough fuel to get to Endeavor naval base.
Recovered 20 of 42 Collectibles.
Your respect for the dead earned you access to Griffin's special weapons stash.
Found and activated the fuel pump.
Drove from Anvil Gate to Mercy.
Maxed the Consecutive Match Bonus in Versus multiplayer.
Reached level 15.
Reached level 10.
Defeated the Lambent Berserker.
Defended Anvil Gate from the Locust siege.
Arrived safely, kinda, at Anvil Gate.
Grabbed a Locust Gas Barge to travel to Anvil Gate.
Completed the first 12 waves of Beast.
Completed one match in all six Versus multiplayer modes.
Executed an infected player and is now turning Lambent.
Reached level 5.
Killed 10 enemies in Team Deathmatch.
Discovered the location of Adam Fenix.
Blew up the Lambent Leviathan from the bridge.
Defended and escaped from Cougar Stadium.
Recovered 5 of 42 Collectibles.
Found food and ammo in Hanover.
Defended the Raven's Nest from Lambent Leviathan.
Woke up from a bad dream.
Your skill and experience means you’re ready for Standard Versus multiplayer.
Reach level 100 and earn every Onyx medal.
Found new places to destroy all humans.
We are the elite Onyx Guard!
Showed your friends the Horde Command Pack sights.
Good ROI on that Silverback upgrade.
The Hammer of Dawn is now online!
As RAAM, made sure Minh never forgets that day outside the House of Sovereigns.
Completed "RAAM's Shadow" in 4 player co-op.
Completed "RAAM's Shadow" in Arcade Campaign.
Used the Mauler shield to kill 10 Gears that had the temerity to fire upon you and your General.
Completed "RAAM's Shadow" in Standard Campaign.
Ignored all Loader safety guidelines and killed 10 Locusts.
Showed 50 Locusts the meaning of sky-fire with HOD Command Center.
As RAAM, ripped 50 Gears to shreds with your Kryll.
Honored the memory of Zeta Squad in 10 matches of Versus.
Defeated the first 10 waves of Horde with every member of Zeta in your party.
Level 100 and going back for more!
Won a Versus multiplayer match as a team of five Recruit Claytons (any mode).
Won a Versus multiplayer match as a team of five Savage Marauders (any mode).
Completed all 12 waves of Beast on all Fenix Rising maps.
Completed all 50 waves of Horde on any of the Fenix Rising maps.
Achieve level 100 a second time and choose to re-up for another tour.
Earned all 132 combat ribbons.
The $!*@# was taken down with extreme force.
Completed all 50 waves of Horde on any of the Forces of Nature maps.
Still standing after 20 waves - you're a natural!
Maxed out all of the Horde fortifications.
Cleaved 25 enemies with a hidden weapon.
Completed all 12 waves of Beast on all Forces of Nature maps.
Guardian is back!
Found the right man for the job!
Captured and "released" 20 opponents as the Savage Hunter.
Led by example and killed 10 opponents as Guardian leader.