Here’s a big one. While I love many first edition and basic Dungeons & Dragons books for many reasons, the Monstrous Compendium is perhaps the first I love as a tool. From this binder sprang my hobby of trying to kill my friends with the coolest monsters, in the weirdest ways possible.

The first cool thing about the Compendium is the cover. So clean, so white. That blue, so official looking. Next is the trio of monsters themselves, leaping out of limbo to Eff. You. Up. And what a group. These aren’t just any monsters. These weirdos are D&D monsters (well, the displacer beast is a rip-off of A. E. van Vogt alien, but whatever). Jeff Easley’s beholder has yet to be matched.
The next important thing that the book isn’t a book, but an oversized binder. That’s very important to its appeal. A binder says, “This book isn’t finished.” Unlike the Monster Manuals, the Monstrous Compendium promised MORE. Also, loose leaf binders tap into a minor obsession I have with office supplies (which I suspect many DMs share). The process of selecting monsters, removing their sheets and compiling them with your adventure notes feels a bit like choosing your weapons for a duel…
You’ll note I’ve not included any of the interior art. That’s partly because I am saving that for something fun for a later date and partly because, after many years, I realized that you could combine Volume One, Two and the first Forgotten Realms sheets into one alphabetical beast of a compendium and I am not entirely sure what goes with what at this point. Does the idea of that fill you with horror? Chew me out in the comments.