Full list of all 47 Army of TWO achievements worth 1,250 gamerscore. It takes around 40-50 hours to unlock all of the achievements in the base game on Xbox 360.
The base game contains 37 achievements worth 1,000 Gamerscore, and there are 2 DLC packs containing 10 achievements worth 250 Gamerscore.
Complete all missions as a Professional.
Complete all missions with the Partner AI.
Kill 75 enemies while in the stealth mode of Overkill.
Kill 100 enemies while in the power mode of Overkill.
Kill 25 Martyrs by shooting the Bomb Packs on their chests.
Kill 50 enemies total in Co-op Riot Shield.
Earn one million dollars in total over the course of campaign mode.
Kill 250 enemies total using SMGs.
Kill 30 enemies using the Riot Shield melee attack
Kill 25 enemies total using RPGs.
Kill 25 Heavy Armor enemies.
Kill 250 enemies total using Shotguns.
Purchase the MP7, M134, DAO-X Protecta, MGL MK-X, and the M107 Light Fifty.
Collect all of the information cases in the entire game.
Kill 250 enemies total using Machine Guns.
Completed Mission 6 as Contractor or higher.
Kill 5 enemies total using Co-op Snipe.
Kill 150 enemies total using Handguns.
Purchase every mask variant.
Kill 100 enemies total using Sniper Rifles.
Kill 50 enemies total in Back-to-Back.
Completed Mission 5 as Contractor or higher.
Drag and heal your partner 25 times.
Kill 250 enemies total using Assault Rifles.
Kill 50 enemies total using the Melee Attack.
Completed Mission 4 as Contractor or higher.
Purchase 3 weapons.
Completed Mission 3 as Contractor or higher.
Completed Mission 1 as Contractor or higher.
Spend 1 minute straight at full Aggro.
Completed Mission 2 as Contractor or higher.
Heal your partner for the first time. Training does not count.
Finish playing a versus ranked match.
Complete 20 minor objectives in a ranked match.
Complete a ranked match without ever needing to be revived.
Earn one billion dollars in total in ranked matches.
Win a ranked match without purchasing any additional weapons.
Win every stage of a ranked three round SSC Challenge match
Destroy 500 barrels in ranked SSC Challenge matches
Win a ranked SSC Challenge match
Achieve 75% accuracy at the conclusion of a ranked three round SSC Challenge match
Kill Dalton in less than 40 seconds
Final blow to Dalton is a headshot with a pimped .44 MODEL 29 handgun
Completed Mission 8 as Professional.
Completed Mission 7 as Professional.
Buy the 'pack 8' gun pack in a multiplayer ranked match
Destroy 300 destructible objects in Mission 7,8