Reflecting on Process

In the previous post, I talked about a number of principles I intended to follow in establishing my core set of monsters: only including widely recognizable monsters, no stat blocks for ordinary animals, keeping variations to a minimum, excluding non-Western monsters (for now), and keeping fantasy "folk" and humanoid NPCs out of the list. This has resulted in a final tally of 317 unique monsters, many of which have a number of variations within them so that a GM can deploy a gaseous undead "Eye Tyrant" with little effort.

This first pass against the list took an excruciatingly long time, because it involved determining what sort of abilities each monster should have (normalized in an insane spreadsheet with lots and lots of formulas), how I want to present them in a neutral fantasy context (via setting-agnostic lore), and developing what variation "tags" made sense for each monster such that expected concepts could be constructed from a monster template like Legos (which naturally resulted in lots of types of goblins...). The most difficult challenge developing a bestiary of this scale posed, however, is its interconnectedness: no monster can be developed in isolation, when all monsters draw from the same pool of standardized abilities.

On Perks and Pain

For example, drafting a monster might surface details like: this monster regenerates, and it seems to be able to evoke terror with its roar, and it's really fast. Which is great and relatively straightforward, but then you have to abstract those abilities into perks that other monsters might also use. Many monsters regenerate. So do we establish "Regenerates +1" and "Regenerates +2", that way we can re-use it? In the same way, many monsters have a roar that stupefies, so do we make "Terror Roar" an ability that can be used by multiple monsters? In a modular system, the goal is to atomize everything as much as possible, so that we don't end up with one-off mechanics, and we maximize the reusability of those mechanics across the whole bestiary.

This, of course, required me to make at least two passes against the initial drafting of the bestiary: one to discover and normalize the monster list with expected abilities, then another to abstract those abilities into a formal set that reduces duplication and redundancy. Which means time. Lots of time. Time spent staring at an insane spreadsheet. Time spent cross-referencing, cleaning up, deleting, reconsidering. Time lost to my real-world work responsibilities. The bestiary, as a component of OSR+, engages all aspects of the system, as monsters have not only their own unique perks, but can have spells, stances, deeds, skills, ethos, languages, HP/MP/AP/DEF/SOAK—they're the system's kitchen sink. Its final boss.

To be clear: this is not a boo-hoo, poor me post! I did this to myself, after all. But going through this process has showed me how all these moving pieces come together and must be carefully considered as a whole rather than as separate pieces. Modularity is key to making it all work. And like I learned with developing OSR+'s ethos system and dissecting the traditional 9 alignments of D&D, there are things fundamental to the design of a monster in the roleplaying context that you only realize when you dissect the entire catalog.

But First... Here's Where We're At

Okay. So brass tacks. We have 317 monsters. What else?

• Still 7 monster types. I'm smug in having confirmed my theory that the 7, in combination with each other, are all we need to classify every fantasy monster conceivable. Again, I challenge you to find an outlier. (And yes I realize my smugness might suggest my "theory" is not falsifiable, but whatever this isn't science anyway!)
• 618 perks. This is the master list of abilities that all monsters draw from, inclusive of legendary talents—which are really powerful perks that only particularly scary monsters get—and weaknesses.
• 37 tags. These are ways to sort monsters, like "Genie" or "Insectoid" or "Demonic." Tags may impart perks. They're a means for GMs to create variations of their own with little effort, or to discover monsters by vibes.
• Over 100 variations of the 317 monsters. These are additional monsters that are treated as "children" of any given monster. For example, to stick with the "Eye Tyrant" example: there are 13 variations of it (as of the time of this writing): Antimagic, Aquatic, Astral, Clockwerk, Gaseous, Polymorphic, Psychic, Sentinel, Spectral, Temporal, Undead, Vampiric, and Vorpal. These variations really just have different abilities, but they're an exercise in showing GMs how you can get a lot of juice out of a single monster concept by just assigning tags to it or mixing up its abilities.
• New mechanics, like how a monster's size (tiny, swarm, personal, melee, or encounter) affects how it interacts with the scene. For example, all attacks of encounter-sized monsters (think Kaiju) can cause siege damage and affect a melee space; they're immune to the advantages that flying opponents enjoy; and can cause knockdown with every attack that also moves victims a number of personal spaces equal to their Mighty.
• A revised Monster Maker. The Character Creator has been completely revamped, so now you can launch it as a Character Creator to make heroes, or you can launch it as a Monster Maker to create custom NPCs or monsters. This took many months of rooting around in a codebase I wrote while on a lot of caffeine and dreams and cursing myself for the horrors I left behind as a result. The ability to create custom monsters will likely be gated as a premium feature, but all 317 monsters will be available on the website and you can even export them in printable NPC Shorthand for use at the table!
• And behind the scenes, automation that allows me to mass-import all the monsters from my insane spreadsheet and into the website, which makes adding or revising monsters as simple as changing values in a spreadsheet and hitting import.

All this sounds great, so where is the bestiary? When do you get to see it?

What's Next for the Bestiary

While the hard work—which in my opinion is all that research and normalization—is done, the practical execution now begins. This is where I roll up my sleeves and dust off my writing degrees to put them to good use.

• Every monster needs a description of its lore, and GM advice about how to run it. The advice contains specifics that perks may reference (for example, a monster might have "Reality Bubble", which is an ability that describes the monster as having an aura that literally changes the environment due to the monster's weirdness. And while the ability has a standard mechanical description, how exactly the monster's aura changes the environment is left up to its description. For example, one monster might make the environment illusory, whereas another might transform the very ground it walks on into flesh. So these descriptions are vital to each monster's definition, even if they only amount to 2 paragraphs of text (times 317).
• Every ability needs to be formally written out. The vast majority of them already have enough notation in my spreadsheet to just be lightly edited into their final form, but many others, while obvious on their face ("Breathes Underwater"), still need text. So if every perk is one or two sentences long, that's 1,236 sentences to write.
• Art! Half the evocativeness of monsters are in how they're depicted. We are proponents of AI generated art at OSR+, so we rely on tools like ComfyUI running Stable Diffusion models like SDXL or Black Forest Lab's new Flux model to create art. Generating the images for all 317 monsters (and their variations) is probably the easiest of these tasks, albeit time-consuming, because we've already developed LoRAs and other generative techniques to get the exact style we want for the system.

My hope is that we'll have these things in place before PAX Unplugged this year (November 2025!), so the clock is ticking.

Wish me luck...

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