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 Bronze "Force Multiplier" medal.
Executed your enemies with variety and style.
Reached level 50.
Recovered all 42 Collectibles.
Recovered all 15 COG Tags.
Completed all campaign Acts on Hardcore Difficulty.
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.
Completed all campaign Acts on Casual or Normal Difficulty.
Killed Myrrah.
Rescued Adam Fenix from captivity.
Turned off the Maelstrom device.
Earned the Bronze "Loot Courtesan" medal.
Survived all 50 waves of Horde.
Completed 5 Arcade Campaign chapters in co-op.
Passed under the Maelstrom and found Azura.
Launched the sub.
Found enough fuel to get to Endeavor naval base.
Your respect for the dead earned you access to Griffin's special weapons stash.
Found and activated the fuel pump.
Recovered 20 of 42 Collectibles.
Drove from Anvil Gate to Mercy.
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.
Discovered the location of Adam Fenix.
Blew up the Lambent Leviathan from the bridge.
Reached level 25.
Defended and escaped from Cougar Stadium.
Found food and ammo in Hanover.
Recovered 5 of 42 Collectibles.
Earned an Onyx medal.
Defended the Raven's Nest from Lambent Leviathan.
Woke up from a bad dream.
Maxed the Consecutive Match Bonus in Versus multiplayer.
Reached level 15.
Wreaked vengence upon humanity!
Completed the first 12 waves of Beast.
Completed one match in all six Versus multiplayer modes.
Reached level 10.
Survived the first 10 waves of Horde.
Reached level 5.
Killed 10 enemies in Team Deathmatch.
Executed an infected player and is now turning Lambent.
Your skill and experience means you’re ready for Standard Versus multiplayer.
Earn the Silver "Number 1" medal.
Reach level 100 and earn every Onyx medal.
We are the elite Onyx Guard!
Showed your friends the Horde Command Pack sights.
Found new places to destroy all humans.
Good ROI on that Silverback upgrade.
The Hammer of Dawn is now online!
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.
Completed "RAAM's Shadow" in Standard Campaign.
As RAAM, made sure Minh never forgets that day outside the House of Sovereigns.
Used the Mauler shield to kill 10 Gears that had the temerity to fire upon you and your General.
As RAAM, ripped 50 Gears to shreds with your Kryll.
Completed "RAAM's Shadow" in Arcade Campaign.
Completed "RAAM's Shadow" in 4 player co-op.
Defeated the first 10 waves of Horde with every member of Zeta in your party.
Completed all 12 waves of Beast on all Fenix Rising maps.
Completed all 50 waves of Horde on any of the Fenix Rising maps.
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).
Achieve level 100 and choose to re-up for another tour of duty.
Achieve level 100 a second time and choose to re-up for another tour.
Earned all 132 combat ribbons.
Maxed out all of the Horde fortifications.
Guardian is back!
Captured and "released" 20 opponents as the Savage Hunter.
Completed all 12 waves of Beast on all Forces of Nature maps.
Cleaved 25 enemies with a hidden weapon.
Led by example and killed 10 opponents as Guardian leader.
The $!*@# was taken down with extreme force.
Completed all 50 waves of Horde on any of the Forces of Nature maps.
Found the right man for the job!
Still standing after 20 waves - you're a natural!