The Dungeons & Dragons 2024 Monster Manual, not launching until February 18, 2025 (actually), is a "chonky book," according to designers Jeremy Crawford and Chris Perkins. I'm apt to agree with them. The 2014 5th Edition Monster Manual had over 350 creatures in it. The 2024 Monster Manual will have over 500. And 75 of those are new to the Monster Manual.
Mind you, some of those 500 creatures will be variations on a theme. Take dragons for example. Each dragons has major stages of life that warrant separate stat blocks for each. From wyrmling (the youngest) red dragon, to a young red dragon, to adult red dragons, to its final form: the ancient red dragon. To oversimplify, a red dragon starts out with an Armor Class 17 and 75 hit points. By the time it reaches boomer status as an ancient, it's rocking an AC 22 and 546 hp. And as far as D&D is concerned, those four life stages equal four creatures.
Dragons are an edge case, however, and the vast majority of creatures found in a Monster Manual are one-offs. If you meet a baby zombie or an adult zombie, they have the same statistics. That's probably an awful example and I immediately regret thinking of it. On second thought, I might not be that far off, as Crawford sites examples of new lower-Challenge-Rating versions of creatures that allow your dungeon master to throw them at their table of players at a sooner level than the original. Plus there's mention of more powerful versions of even the apex versions of creatures in the original 2014 5e Monster Manual.
So, perhaps, there are fledgling vampires, vanilla vampires, and ancient and even scarier vampires to be found among the 75 "new" creatures in the 2024 Monster Manual. I don't mind this approach. It's vaguely like "level scaling" in video games, where the creatures you meet at any level are meant to provide a challenge for players. So at 1st level you might meet that baby zombie, and at 5th level you take on a baby-daddy zombie. Again, my examples are terrible and I continue to regret their use.
The ooze category of monsters now has a higher Challenge-Rating version called the Blob of Annihilation. I've never been into oozes, but that name is amazing. It can also dissolve entire towns at a time, which is horrific, but that name is still ace.
All of the art is new. Which is absolutely nuts. There's so much artwork in a Monster Manual as is. But it's wonderful that Wizards of the Coast is at least putting on a good show that it's paying its artists well, and that WotC's overlord, Hasbro, isn't replacing real artists with generative AI. Right, Hasbro? Right?
Wizards of the Coast declared some time ago that no one major printing house could keep up with WotC's upcoming schedule of book printings. Cranking out thousands of 384-page core rulebooks is apparently a tall order. So, again, the 2014 Monster Manual got pushed back to February 18, 2025, on the launch calendar.