What's that?

While exploring the swamps of ECU, I discovered a strange object. what is this?




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It's my first time uploading a thread, so it's a bit awkward

 

a monolith, its also found in real life, people say its put in places by aliens, but I think the devs added this in game just as a easter egg.

 

The devs have a running gag where they sometimes hide this monolith around maps on an update, then remove it the next update. It has appeared in JRI and Utah too iirc.