Green as Grass
Train the rook (any difficulty)

It's a Trap!
Story progression in Act 1, Chapter 2

Escort Service
Story progression in Act 1, Chapter 4

Girl About Town
Story progression in Act 1, Chapter 6

That Sinking Feeling
Story progression in Act 2, Chapter 4

Freebaird!
Story progression in Act 2, Chapter 5

Heartbroken
Story progression in Act 2, Chapter 6

Longitude and Attitude
Story progression in Act 3, Chapter 3

Tanks for the Memories
Story progression in Act 3, Chapter 4

Water Sports
Story progression in Act 3, Chapter 6

There's a Time for Us
Story progression in Act 4, Chapter 2

Better Wrapped in Beacon
Story progression in Act 4, Chapter 3

Have Fun Storming the Castle
Story progression in Act 4, Chapter 6

And the Horsey You Rode in On
Story progression in Act 5, Chapter 1

You Are the Support, Son
Story progression in Act 5, Chapter 2

Brumak Rodeo
Story progression in Act 5, Chapter 4

Does This Look Infected to You?
Story progression in Act 5, Chapter 5

Tourist of Duty
Complete all campaign acts on Casual Difficulty

Guerilla Tactician
Complete all campaign acts on Normal Difficulty

Artist of War
Complete all campaign acts on Hardcore Difficulty

Suicide Missionary
Complete all campaign acts on Insane Difficulty

Collector
Recover 5 collectibles (any difficulty)

Pack Rat
Recover 20 collectibles (any difficulty)

Completionist
Recover all 41 collectibles (any difficulty)

One-Night Stand
Complete 1 chapter in co-op on any difficulty (Marcus or Dom)

Open Relationship
Complete 10 chapters in co-op on any difficulty (Marcus or Dom)

Friends with Benefits
Complete all acts in co-op on any difficulty (Marcus or Dom)

Once More, With Feeling
Perform 30 perfect active reloads (any mode)

Takes a Licking
Melee 30 Tickers (any mode)

Organ Grinder
Kill 30 enemies with a cover mounted Mulcher (any mode)

Shock and Awe
Kill 30 enemies with the heavy Mortar (any mode)

Said the Spider to the Fly
Kill 10 enemies with a planted grenade (any mode)

Crowd Control
Melee 10 enemies down with the Boomshield equipped (any mode)

Smells Like Victory
Kill 30 enemies with the Scorcher Flamethrower (any mode)

Variety Is the Spice of Death
Kill an enemy with every weapon in the game (any mode)

Seriously 2.0
Kill 100,000 enemies (any mode)

Standing Here, Beside Myself
Win 3 matches of Wingman (public)

Beat the Meatflag
Capture 10 meatflags in Submission (public)

It's Good to be the King
Win 10 rounds of Guardian as the leader (public)

You Go Ahead, I'll Be Fine
Win three matches of King of the Hill (public)

Back to Basic
Successfully complete the 5 lessons of multiplayer Training Grounds

Party Like It's 1999
Play 1999 rounds of multiplayer (any mode)

Around the World, Again
Win a multiplayer match on each map (any mode)

Dirty, Dirty Horde
Survive the first 10 waves of Horde (any difficulty, any map)

Hoard the Horde
Survive all 50 waves of Horde (any difficulty, any map)