My purchased copy of the
MM does not reference a "Primordial Colossus". It references the Godforged Colossus, which does exist. Likewise, the index correctly lists Dusk Unicorn. I haven't checked every entry to see if the printed books match the errata list, but it's obvious the PDFs were not final versions.
To be useful, this list should contain errors which only made their way into the actual print books.
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