How to Unlock the M4 JAK Harbinger Kit in MW3 & Warzone
The JAK Harbinger is the newest aftermarket upgrade available for Modern Warfare 3 and Warzone players as of the opening week of Season 4. This conversion kit transforms the M4, a fan-favorite fully automatic Assault Rifle from Modern Warfare 2, into a semi-auto Marksman Rifle packing an even deadlier punch.
Here’s how you can easily obtain the JAK Harbinger kit for your M4 during Season 4!
Related: Best JAK Harbinger M4 Loadout & Class Setup for MW3
How to Get the New JAK Patriot Kit in MW3 & Warzone
To unlock the new JAK Harbinger conversion kit for the M4, players must complete any five weekly challenges from Week 1 of Season 4.
Each mode—Multiplayer, Zombies, and Battle Royale (Warzone)—offers seven challenges, giving you a grand total of 21 challenges to pick from. Simply ace any five of these challenges, and voilà! The JAK Harbinger Kit is yours as the ultimate reward!
All Call of Duty: Season 4 Week 1 Challenges
Below is a quick rundown of this week’s challenges across each mode:
| MULTIPLAYER | ZOMBIES | WARZONE |
|---|---|---|
| Get 40 kills shortly after sprinting with a recommended assault rifle. | Get 300 kills while ADS with a recommended assault rifle. | In Warzone, open 75 loot caches. |
| Get 25 kills with a recommended weapon after having recently swapped weapons. | Get 150 kills with a recommended weapon after having recently swapped weapons. | In Urzikstan, kill 15 operators in the northwest region (Resort, Power, Seaport, Cargo). |
| Get 20 sliding or midair kills with recommended assault rifles. | Get 3 Disciple kills with a recommended weapon. | In Urzikstan, kill 15 operators in the southern region (City, Suburbs, Manor). |
| Get 20 kills with iron sights equipped to a recommended marksman rifle. | Get 100 hipfire kills with a recommended SMG. | Complete 15 Contracts. |
| Kill 15 enemies who are blinded or stunned with recommended assault rifles. | Get 200 kills with Cryofreeze ammo installed on a recommended assault rifle. | In Urzikstan, kill 15 operators in the eastern region (Military Base or Farms). |
| Finish 10 matches with 3+ players in your party. | Get 300 kills with a Pack-A-Punched recommended weapon. | In Urzikstan, kill 15 operators in the central region (Old Town, Low Town). |
| Get 2 long-range throwing knife or sticky kills. | Get 100 kills with a melee weapon. | In Warzone, place in the top ten 7 times. |
Once you’ve tracked down and completed your selected challenges, the JAK Harbinger Kit will be unlocked for your M4, ready to be equipped (from the Blacksmith) in your preferred playlists across both Modern Warfare 3 and Warzone.