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.
Earned the Silver "Number 1" medal.
Recovered all 42 Collectibles.
Recovered all 15 COG Tags.
Completed all campaign Acts on Insane Difficulty.
Completed all campaign Acts on Hardcore Difficulty.
Earned the Bronze "Force Multiplier" medal.
Complete all Acts in 4 player Co-op on any difficulty.
Reached level 50.
Executed your enemies with variety and style.
Survived all 50 waves of Horde.
Complete all Acts in Co-op on any difficulty.
Earned an Onyx medal.
Your respect for the dead earned you access to Griffin's special weapons stash.
Launched the sub.
Completed all campaign Acts on Casual or Normal Difficulty.
Killed Myrrah.
Rescued Adam Fenix from captivity.
Turned off the Maelstrom device.
Passed under the Maelstrom and found Azura.
Maxed the Consecutive Match Bonus in Versus multiplayer.
Reached level 25.
Found enough fuel to get to Endeavor naval base.
Recovered 20 of 42 Collectibles.
Found and activated the fuel pump.
Drove from Anvil Gate to Mercy.
Defeated the Lambent Berserker.
Completed 5 Arcade Campaign chapters in co-op.
Defended Anvil Gate from the Locust siege.
Arrived safely, kinda, at Anvil Gate.
Grabbed a Locust Gas Barge to travel to Anvil Gate.
Discovered the location of Adam Fenix.
Completed one match in all six Versus multiplayer modes.
Earned the Bronze "Loot Courtesan" medal.
Killed 10 enemies in Team Deathmatch.
Reached level 15.
Executed an infected player and is now turning Lambent.
Wreaked vengence upon humanity!
Reached level 10.
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.
Completed the first 12 waves of Beast.
Reached level 5.
Survived the first 10 waves of Horde.
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.
We are the elite Onyx Guard!
Found new places to destroy all humans.
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.
Showed 50 Locusts the meaning of sky-fire with HOD Command Center.
Ignored all Loader safety guidelines and killed 10 Locusts.
Honored the memory of Zeta Squad in 10 matches of Versus.
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.
As RAAM, ripped 50 Gears to shreds with your Kryll.
Completed "RAAM's Shadow" in 4 player co-op.
Completed "RAAM's Shadow" in Arcade Campaign.
Defeated the first 10 waves of Horde with every member of Zeta in your party.
Level 100 - so nice, I did it twice.
Level 100 and going back for more!
Won a Versus multiplayer match as a team of five Savage Marauders (any mode).
Won a Versus multiplayer match as a team of five Recruit Claytons (any mode).
Completed all 50 waves of Horde on any of the Fenix Rising maps.
Completed all 12 waves of Beast on all Fenix Rising maps.
Earned all 132 combat ribbons.
Led by example and killed 10 opponents as Guardian leader.
Completed all 12 waves of Beast on all Forces of Nature maps.
Completed all 50 waves of Horde on any of the Forces of Nature maps.
Still standing after 20 waves - you're a natural!
The $!*@# was taken down with extreme force.
Captured and "released" 20 opponents as the Savage Hunter.
Cleaved 25 enemies with a hidden weapon.
Guardian is back!
Found the right man for the job!
Maxed out all of the Horde fortifications.