Full list of all 70 Gears of War: Judgment achievements worth 1,500 gamerscore. It takes around 50-60 hours to unlock all of the achievements in the base game.
The base game contains 50 achievements worth 1,000 Gamerscore, and there are 2 DLC packs containing 20 achievements worth 500 Gamerscore.
Achieved level 50 a third time and chose to re-up for another tour
Attained all Stars on Insane Difficulty
Attained 100 Stars on at least Hardcore Difficulty
Achieved level 50 a second time and chose to re-up for another tour
Attained 75 Stars on at least Normal Difficulty
Won 10 rounds of Team Deathmatch
Won a match on every map in all Versus modes
Won one match on every map in Free For All
Played any section in 4 player Co-Op
Recovered all 48 COG Tags during the Campaign
Won one match in Free For All, Team Deathmatch, and Domination
Completed all Declassified Missions on Insane difficulty
Completed all Campaign Chapters in Co-op
Completed all Campaign Chapters on at least Normal difficulty
Completed all Campaign Chapters on at least Hardcore difficulty
Completed all Campaign Chapters on Insane difficulty
Completed wave 10 on all maps in Survival mode
Achieved level 50 and chose to re-up for another tour of duty
Reached level 50
Won one match on every map in Domination
Won 10 matches of Overrun
Completed all Declassified missions
Completed Aftermath
Earned at least one Onyx medal
Won one match on every map in Overrun
Won one match on every map in Team Deathmatch
Killed with all classes of Locust in Overrun
Killed with all classes of COG in Overrun or Survival
Reached level 40
Completed all Campaign Chapters on at least Casual difficulty
Completed Courthouse
Recovered 25 COG Tags during the Campaign
Completed Downtown Halvo Bay
Completed Onyx Point
Completed at least 20 Declassified missions
Completed Seahorse Hills
Attained 50 Stars on at least Casual Difficulty
Unlocked Aftermath
Recovered 10 COG Tags during the Campaign
Completed Halvo Bay Military Academy
Completed Museum Of Military Glory
Earned 3 unique Ribbons in any section
Completed your first Declassified mission
Watched Aftermath teaser
Equipped your first Medal
Reached level 5
Reached level 10
Reached level 20
Reached level 30
Earn the Onyx "War Supporter" medal
Won Hardcore Survival on Terminal with 5 Soldiers
Killed 100 enemies with each Locust
Revived 100 total teammates on Terminal as a Medic
Got a Double while emerging as a Corpser
Earned 50 Double ribbons with the Booshka on Terminal
Played 10 matches total on BloodDrive
Placed first in Free For All in Boneyard 5 times
Earned a killing spree with the Boomshield on Boneyard
Earned the You’re It ribbon on Boneyard
Won a Team Death Match game with the entire team wearing the Car 13 Armor skin
Won a TDM, DOM, and BT match with your entire team wearing the UIR Armor skin
Won public/ranked game of Execution on Museum with all players using Gold character and weapon skins
Finished wave 10 of Survival at the first e-hole on Ward on at least Normal difficulty
Got a kill with each pickup weapon in FFA during a single game on the map Lost City
Scored a flag cap on Streets, Rig, Gondola, Library, Lost City, Museum, and Checkout
Killed the flag carrier a total of 20 times
Scored 5 flags in BT as Paduk
Got a multi-kill while playing as an enraged Rager on Ward
Earned the Tree House Predator ribbon on Ward
Destroyed the generator in under 8 minutes on any DLC map