Full Gameplay Walkthrough...

Complete the indicated task to unlock the achievement.

Achievement	How to unlock
...The Harder They Fall	Unlock during Act 3 of the Campaign.
Best I Can Do Is a Pizza Party	Complete any hundred Secondary Objectives in Horde Siege.
Brotector	Save another player from a struggle with a Locust.
Chainsaw Go Brrrrrrrrr	Let a chainsaw do what it does best against a Locust in Campaign or Horde Siege.
Crepe du Raven	Carefully inspect the underside of a Raven in Horde Siege.
Days Since Last Accident: 0	Commit a workplace safety violation on Battleship in Versus.
Dead Serious	100% Campaign on Insane, 25,000 kills in Versus, max Player Level, and max four classes.
Down, but Not Dead	Revive 250 squadmates from DBNO with the Stim Vaporizer in Horde Siege.
Emergence Begins	Unlock during Act 1 of the Campaign.
End of the Line	Unlock during Act 4 of the Campaign.
Explosive Indigestion	Play a game of explosive cornhole with a Bilefrog.
FNG	Complete Boot Camp.
Field Service	Reach Player Level 100 and Re-Up for the first time.
For My Boys	Unlock during Act 5 of the Campaign.
For Whom the Bell Tolls	Beat the Campaign on Insane difficulty, achieve 100% completion (Any difficulty)
Form-Up!	Receive the max reward from a Perk Cache in Horde Siege (any difficulty).
Get Back You Eight-legged Freak	Unlock during Act 3 of the Campaign.
Got Your Wings	Re-up for the final time and claim your wings.
Got to the Choppa	Unlock during Act 2 of the Campaign.
HEY NOW, YOU'RE AN ALL STAR...	Get 25,000 kills in Versus.
I Am Heavy Weapons Guy	Kill ten enemies in a row using a single detached turret.
I Didn't Hear No Bell	Save your entire squad while you're moments from death in Horde Siege.
I WILL MASSACRE YOU	Kill 50,000 Enemies in Horde Siege (any difficulty).
I'm All Amped Up	Maintain thirty seconds of Adrenaline with the Injector in Horde Siege.
It Only Game, Why You Heff to Be Mad?	Win a game of Conquest without the enemy team scoring.
Just Let Me Get One More...	Get hundred Revives.
Lift Outta Hell	Complete and Survive fifty Horde Siege Missions (Infantry difficulty or higher).
Like a Boss	Successfully complete twenty-five Invasion Events in Horde Siege (any difficulty).
Memories From E-Day	Find all Collectibles in the Campaign (any difficulty).
Never Fight Alone	Extract from Horde Siege with all squadmates alive on Allfather difficulty.
Nothing Left but the Fight	Unlock during Act 5 of the Campaign.
Okay, Boomer	Carve-up a Boomer.
Payback's A Pitch	Take revenge on an Armored Wretch that stunned you.
Quartermaster	Unlock all Supply Cache items in the Campaign.
Relax. I'm the Map	Discover all Hard Cases in the Campaign.
Remember Kalona	Complete all Acts of the Campaign (any difficulty).
Right in the Ticker	Convert a Ticker to express air mail and return to sender.
Side Piece	Complete all secondary objectives in the Campaign (any difficulty).
Siege Specialist	Reach max level with the Assault, Breacher, Marksman, and Medic classes in Horde Siege.
Somebody Set Us Up the Bomb	Plant the bomb in Demolition and have it explode without the enemy defusing it.
Spotted and Slotted	Pulse 1,000 enemies with the Pulse Drone in Horde Siege.
Stacks, On Stacks, On Stacks	Spend 150,000 Energy at the Supply Cache in Horde Siege (any difficulty).
The Bigger They Are...	Unlock during Act 1 of the Campaign.
The Lucky Ones Died on E-Day	Earn all other Achievements.
The Only Good Bug is a Dead Bug	Unlock during Act 4 of the Campaign.
The Scorched Legion	Unlock during Act 2 of the Campaign.
This Is My Rifle	Unlock all Weapon Mods in Horde Siege.
Today We Are Canceling the Apocalypse	Complete all Acts of the Campaign on Insane difficulty.
Turn It Up to 11	Execute fifty enemies Stunned by the Sonic Disruptor in Horde Siege.
Twice the Pride, Double the Fall	Unlock during Act 3 of the Campaign.
Two Grubs, One Gut-Punch	Show two Grubs what a single Gut-Puncher round can do.
We Must Improvise	Unlock during Act 1 of the Campaign.
Who Loves Ya, Baby?	Revive twenty players from other squads in Horde Siege.
You Want What On the Front of a Gun?!	Unlock during Act 2 of the Campaign.
You're My Brother	Complete all Acts of the Campaign on Co-Op (any difficulty).