Botw Wux File ^new^ -

But if you’re a modder, a dataminer, or just curious about how Breath of the Wild works under the hood, understanding .wux is your first step. It’s the glue holding Hyrule together—one packaged archive at a time.

If you search online, you’ll also find .wux as a format for (used in emulators like Cemu). That’s a different thing entirely: botw wux file