Just Cause 4 Multiplayer

Just Cause 4 Multiplayer is the multiplayer mod for Just Cause 4.

JC4MP (April Fools 2021) — This Discord post is from April 1, 2021.

Development history[]

Multiplayer is not natively a part of the game. This is only possible thanks to community efforts in modifying.

Due to various technical difficulties, it was initially believed to be impossible to make a multiplayer for this game.

As of some time in 2024, this mod began to be developed. The mod was announced on January 13, 2025.

The second teaser video revealed that it would be finished in october 2025.

Description[]

It was launched on october 1, 2025.

Most recent information and download link at the official site: jc4mp.com

Quotes from the official site:

"Play Now

Just Cause 4 Multiplayer is a fan-made modification for Just Cause 4 that adds an online multiplayer mode. Explore, destroy, and create chaos with friends."

"Only available for Just Cause 4 for PC on Steam."

"CREATE CHAOS WITH FRIENDS

Team up with players from around the world and unleash destruction together. Whether you're liberating cities, pulling off insane stunts, or just causing mayhem, JC4MP brings the chaos multiplayer was meant for."

Troubleshooting of known bugs[]

The Microsoft Store version of the game might not be compatible with this mod, because attempting to use the "Simple Mod Loader" can produce an error message that shows some random code and claims that "The parameter is incorrect." There is currently no known fix for this.

Gallery[]

Feel free to add something.

Trivia[]

See Just Cause Multiplayer, Just Cause 2 Multiplayer and Just Cause 3 Multiplayer for previous multiplayer mods.
On April 1st 2021, someone made an April Fools prank, telling people they were making Just Cause 4 Multiplayer.
Until January of 2025, this article served as a warning for people that download links for such a mod were a likely scam or virus.