It may be a collection of digital assets, such as high-resolution posters, character bios, or "Limited Edition" covers for a specific project.
Ensure the file is being distributed legally. Many "Limited Edition" releases are sold through official platforms like Comixology, Marvel Unlimited, or Patreon.
If this is a project by a specific artist or writer (e.g., from a Kickstarter or IndieGoGo campaign), checking their official social media or website is the best way to get a legitimate copy.
This could be a "Limited Edition" digital release of a comic book series or a character encyclopedia showcasing Black superheroes from various publishers (Marvel, DC, or independent creators).