While you might not find a fan-made 500-page PDF, DC Comics does publish official collections known as "Compendiums." These softcover editions are designed to be high-value, doorstop-sized books, often clocking in at around 500 pages, and contain complete runs of comic series, similar to what a fan-made compilation would aim to do.
The Ultimate Guide to Finding and Managing Massive DC Comics PDF Collections Online
: Fan-compiled archives, such as a compilation of 130 DC characters, are frequently shared via Google Drive links for easy access. DC Comics Super-Villains (The Complete Visual History)
: This is the official subscription service for DC. It offers a library of over 32,000 comics that you can read on your browser or mobile devices through the App Store or Google Play.
The rest of this guide will focus on the first possibility—large-format collections—and show you how to get them the right way.
Why "500 pages"? Why "Google Drive"?
Collections of 6 to 12 issues bound together, often reaching several hundred pages.