1.Frenzy Killer - Get 5 rapid kills.
2.Mega Killer - Get 6 rapid kills.
3.Ultra Killer - Get 7 rapid kills.
4.Relentless Killer - 20 kills without dying.
5.Brutal Killer - 25 kills without dying.
6.Nuclear Killer - 30 kills without dying using only weapons, field upgrade, and equipment.
7.Circus Act - Get a Bankshot kill with a Combat Axe.
8.Trip Cap - Control all three objectives in Domination for three minutes straight.
9.Gift Horse - Kill an enemy with the Scorestreak you stole from their Care Package.
10.Reverse Card - Kill an enemy with the explosion caused by shooting an enemy piece of Equipment or Field Upgrade.
11. Nuked out - 30 kills without dying in FFA.
12.Same day delivery - Get 2 or more kills a single body shielld explosion.
13.Extreme Precision -Get 5 headshots with a Sniper Rifle without reloading or dying.
14.Castled - 10 kills without leaving one objective zone.
15.Chain Killer - Get 7+ rapid kills.
16.Very Nuclear - Nuke with 25 different Weapons
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1.Undaunted — Survive the horde of Fears in Mission: Suppression
2.Overpowered - In Endgame, earn 1,000,000 total Power.
3.Pest Control - Defeat the Endgame Final Boss (red icon in 4 zone).
4.Exotic Arsenal - Get an elimination with 6 different exotic weapon.
5.Defeat Menendez only with machetes. (Thanks @Shiranui for info)
6.Green Thumb - Kill the boss in the Distortion mission without taking damage.
7.Dream Team - Evacuate from Zone 4 25 times.
8.Monkeying Around:

1.Harbinger of Doom — Get 100 kills with a single Scorestreak
2.Another Round Reach Round 100.
3.Box Addict — Get 30 different guns from the Mystery Box in a single match
4.Countdown — Kill an elite enemy by launching it with a Jump Pad
5.New Main — Kill 1,000 Zombies with each of the eight dedicated Crew Operators
6.Social Distancing - Reach Round 20 without taking any damage.
7.Armed to the Teeth - Have 3 Pack-a-Punch Level 3, Legendary Rarity Weapons equipped with ammo mods and 8 Perks active.
8.Survive to round 100
9.Lucidity - Complete the Tank Dempsey side quest on Ashes of The Damned
10.Zombies Dark Ops Master - Complete 15 Zombies Dark Ops challenges.
11. Ingenuity - Reach round 50 with tbe dragon wings and Lawyers pen relics active
12.Showboat - Complete Ashes of the Damned Main quest at round 100 or more. (Thanks @☆野山猹_Official☆ for info).
13.Invincible — Survive to round 50 without going down.
14.The one - Reach round 999
15.Action Hero - Shoot and kill 100 zombie without reloadding.
16.Boss Rush - Defeat the Ashes of the damned boss fight in 5 min or less.
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18.Serious Monkey Business - Default the Papaback in Harfcore.
19.Anathema - Kill 1000000 Zombies.
20.“The usual, please” - Drink Juggernog 20 times in 1 match.
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The guide is not finished and will be updated.

All Mine - Complete 5 Scavenger Contracts in a single match.
Ascendance - Win 1 Match without dying.
Backlog - Complete 7 Contracts in a single match.
Blind Lead - Get an Elimination using hipfire with a Sniper Rifle.
Deleted - Get 20 Eliminations in a single match.
Efficient Execution - Get 5 One-Shot Eliminations with Sniper Rifles in a single match.
Flawless Feed - Get 4 Eliminations without reloading in a single match.
Gotta Run - Complete 5 Supply Run Contracts in a single match.
Ground War - Get 100 Eliminations with Ground Loot Weapons.
Boom Boom - Get 5 Eliminations with Launchers in a single match.
Chop Chop - Get 1 Eliminations while riding Helecopters.
Holstered - Get 5 Eliminations with Pistols in a single match.
Humbled - Complete 3 Big Game Bounty Contracts in a single match.
Next - Complete 5 Bounty Contracts in a single match.
One Round - Get 100 Headshots.
Repeat Exploder - Get 3 Eliminations by sticking an enemy with a grenade in a single match.
Sliced - Get 5 Eliminations with Melee Weapons in a single match.
The Cleaner - Wipe 50 Squads.
Last Cap Standing - Complete 5 Recon Contracts in a single match.
Make It Stick - Get an Eliminations on a Most Wanted Contract Target with a grenade stick.