You can no longer get the CX-9 or Serac blueprint in Warzone because this version of the game was shut down. However, this guide will be updated and will come in handy if the CX-9 ever returns. It is still available in Black Ops Cold War multiplayer via the in-game challenge.
Fans of Call of Duty Warzone were desperate to unlock the CX-9 SMG back in Black Ops Cold War Season 4. Why? Because early CX-9 Warzone loadouts were looking mighty strong at the time, and also because it had been sitting on the sidelines of Warzone for months. First seen way back in February 2021 during Season 2, a CX-9 blueprint variant called the Serac began accidentally dropping out of loot crates, along with another yet-to-be-released weapon, the RAAL LMG.
Since then, players had been anticipating the CX-9 to release at the start of every new Warzone season, and finally, right at the end of Season 4 on August 3, 2021, it was let loose at last.
Sadly, with the removal of Black Ops Cold War's content, including its arsenal, from Warzone, the CX-9 is no longer available in the battle royale mode. However, it can still be unlocked in the traditional Black Ops Cold War multiplayer offerings, if you fancy a blast to the past in this older CoD title.
CX-9 Warzone unlock
The CX-9 was unlocked in Warzone by completing an in-game challenge that tasked you with getting two longshot kills using an SMG in five different matches.
This unlock challenge could be completed in Warzone or in the Black Ops Cold War multiplayer modes. Given the shorter matches and much more constant action, it was easier to complete this challenge in the multiplayer modes, rather than Warzone. Ironically, now that this content has since been removed from Warzone, it can only be acquired in the standard multiplayer of the older title.
If you didn't want to grind the challenge, a CX-9 blueprint was also available in the store that would let you bypass the unlock challenge.
CX-9 Warzone blueprint
The Serac CX-9 Warzone blueprint was available in the store when it released. You could get it by buying the Soap operator bundle. This would also unlock the weapon for you to use in Warzone and Modern Warfare.
That's how you could get your hands on the CX-9 SMG in Warzone near the end of Black Ops Cold War's time in the spotlight.