How to unlock the JAK Harbinger Kit in MW3 and Warzone

A new season in Modern Warfare 3 means a whole new set of Aftermarket Parts to unlock and equip on a variety of guns in the game.

The JAK Harbinger Kit takes a classic CoD weapon and totally transforms it by swapping out its normal magazine and ammunition for something a lot more powerful. But there are big trade-offs when it comes to fire rate and other stats.

Here’s everything to know about the JAK Harbinger Kit in MW3 and Warzone.

What is the JAK Harbinger Kit in MW3 and Warzone?

The JAK Harbinger Kit is an Aftermarket Part and Conversion Kit for the M4 assault rifle in MW3 and Warzone.

JAK Harbinger is described as a “.50 Cal conversion kit for the M4” and “an extremely deadly, quick-kill weapon” that has a “slow fire rate, drop in bullet velocity, and a significant increase in recoil” that “will require a careful hand.”

It’s one of the more interesting Aftermarket Parts released in recent memory and should be a fun one to mess around with in multiplayer at the very least.

How to get the JAK Harbinger Kit in MW3 and Warzone

To unlock the JAK Harbinger Kit, you must finish any five of the weekly missions from season four, week one in MW3. The challenges can be done in MW3 multiplayer, MW3 Zombies, or Warzone.

Here’s the full list of challenges that can be completed in all modes.

MW3 Multiplayer weekly challenges

• Get 40 operator kills shortly after sprinting with recommended assault rifles.
• Get 25 operator kills with a recommended weapon after having recently swapped weapons.
• Get 20 operator sliding or midair kills with recommended assault rifles.
• Get 20 operator kills with iron sights equipped to a recommended marksman rifle.
• Get 15 kills against operators who are blinded or stunned with recommended assault rifles.
• Finish 10 matches with three or more players in your party.
• Get two long range throwing knife or sticky operator kills.

MW3 Zombies weekly challenges

• Get 300 kills while aiming down sights with a recommended assault rifle.
• Get 150 kills with a recommended weapon having recently swapped weapons.
• Get three Disciple kills with a recommended weapon.
• Get 100 hipfire kills with a recommended SMG.
• Get 200 kills with Frost damage with a recommended assault rifle.
• Get 300 kills with a Pack-a-Punched recommended weapon.
• Get 100 kills with a melee weapon.

Warzone weekly challenges

• In Warzone Urzikstan, get 15 operator kills in the North-West region.
• In Warzone Urzikstan, get 15 operator kills in the Eastern region.
• In Warzone Urzikstan, get 15 operator kills in the Southern region.
• In Warzone Urzikstan, get 15 operator kills in the Central region.
• In Warzone, place in the top 10 seven times.
• In Warzone, complete 15 contracts.
• In Warzone, open 75 loot caches.