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docs/file_formats/W3D_HUB_PATCH.md

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+# W3D Hub Patch
+A W3D Hub Patch
+
+A `.w3dhub.patch` is included in MIX Patch files.
+It contains instructions for updating the target MIX.
+
+JSON file with a static CRC32 of `E6FE46B8`
+
+## Example:
+```json
+{
+  "removedFiles": [
+    "sov_v_mad.gif"
+  ],
+  "updatedFiles": [
+    "sov_v_mad.w3d"
+  ]
+}
+```