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.
Completed all campaign Acts on Insane Difficulty.
Complete all Acts in 4 player Co-op on any difficulty.
Reached level 50.
Recovered all 42 Collectibles.
Earned the Silver "Number 1" medal.
Recovered all 15 COG Tags.
Earned an Onyx medal.
Recovered 20 of 42 Collectibles.
Earned the Bronze "Force Multiplier" medal.
Completed the first 12 waves of Beast.
Wreaked vengence upon humanity!
Earned the Bronze "Loot Courtesan" medal.
Completed all campaign Acts on Hardcore Difficulty.
Executed your enemies with variety and style.
Your respect for the dead earned you access to Griffin's special weapons stash.
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.
Reached level 25.
Maxed the Consecutive Match Bonus in Versus multiplayer.
Turned off the Maelstrom device.
Passed under the Maelstrom and found Azura.
Launched the sub.
Survived all 50 waves of Horde.
Found enough fuel to get to Endeavor naval base.
Found and activated the fuel pump.
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.
Reached level 15.
Discovered the location of Adam Fenix.
Blew up the Lambent Leviathan from the bridge.
Defended and escaped from Cougar Stadium.
Completed 5 Arcade Campaign chapters in co-op.
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.
Survived the first 10 waves of Horde.
Reached level 10.
Completed one match in all six Versus multiplayer modes.
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.
Reach level 100 and earn every Onyx medal.
Found new places to destroy all humans.
Showed your friends the Horde Command Pack sights.
We are the elite Onyx Guard!
Get 500 Silverback rocket kills in Horde (any map, any difficulty).
Achieve Level 4 in Horde Command Center fortifications.
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.
As RAAM, made sure Minh never forgets that day outside the House of Sovereigns.
Ignored all Loader safety guidelines and killed 10 Locusts.
Showed 50 Locusts the meaning of sky-fire with HOD Command Center.
Honored the memory of Zeta Squad in 10 matches of Versus.
Completed "RAAM's Shadow" in Standard Campaign.
As RAAM, ripped 50 Gears to shreds with your Kryll.
Defeated the first 10 waves of Horde with every member of Zeta in your party.
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 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 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.
Cleaved 25 enemies with a hidden weapon.
Captured and "released" 20 opponents as the Savage Hunter.
Found the right man for the job!
Guardian is back!
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.
The $!*@# was taken down with extreme force.
Still standing after 20 waves - you're a natural!
Achieve the maximum level on all fortifications in Horde mode.
Kill 10 opponents as the leader in a round of Guardian on a Forces of Nature map.