After multiple peer reviews, we've got the manuscript for the Core Rulebook dialed in. We've got a couple more revisions to make, then it's off to the editor. Which I am stoked about. We've also got some other creators that I am a fan of, designing monsters for the Encyclopedia Monstergoria, which I am equally stoked about. I'll have more on that soon.
Until then, please enjoy this deep dive into the rules from Geo.
Stay safe out there, and may the dice always roll in your favor.
-JHM
321RPG Deep Dive - Post 2 of 10: One Die to Rule Them All
Hey everyone,
Last month, we talked about Luck Points and how they handle three jobs at once. This week, let's talk about the dice themselves.
The d10-Only System
321RPG runs entirely on ten-sided dice. No d20s, no d6s, no d12s (the oft-neglected die), no percentile dice, no fistfuls of d8s. Just d10s.
Why d10s?
Using a single die type solves real problems at the table:
Less confusion. New players don't need to learn which die to grab for which situation. It's always a d10. No fumbling through the dice bag looking for that elusive d12.
Simpler math. Base-10 is intuitive. When your stats range from 2 to 9, rolling a d10 creates clean percentages. A stat of 7 gives you a 70% chance of success. Easy.
More versatility. One die type means we can use it for everything: skill checks, damage, ammo rolls, and random tables. The system stays consistent.
How It Works: Roll Equal to or Under
Here's the core mechanic: when you attempt an action with an uncertain outcome, you roll a d10 and try to roll equal to or under the relevant stat. The lower you roll, the better.
Your character has a Brains stat of 6? Roll a 6 or lower to succeed at that puzzle. Roll a 1? That's a critical success. Roll an 8? You fail.
This inverts the typical "high roll good" mentality, but it creates something interesting: your stats directly represent your percentage chance of success. It's transparent. Players know their odds before they roll.
Rethinking Combat
Now here's where things get interesting. When coming up with our ruleset, I thought about those iconic d20 rolls that deliver the most dopamine in D&D. But one thing always bothered me: if I needed a 13 to hit a monster and I rolled a 17, I wouldn't necessarily hit the monster harder. I could roll a 19, and it would deal the same damage as a 13. The damage dice would then determine how much hurt I actually inflicted. So I could roll a killer 19 to hit and then roll 2 points of damage. It just didn't make sense to me.
What I realized is that the d20 is, for all intents and purposes, an on-off switch. You either hit or you don't.
Therefore, there's no need to roll to hit at all. Just adjust the damage dice accordingly. And then, to keep it consistent and give players agency, we made sure every character gets two attacks per turn. That way you can still do something meaningful in the round even if you “miss” one attack.
In 321RPG, combat reverses the roll-under mechanic. When you roll damage, higher is better.
Every attack automatically hits. What matters is how much damage you deal. You roll a d10, then add or subtract your weapon's DMG rating.
A handgun has DMG -3. Roll a 10? That's 10 - 3 = 7 damage. Roll a 3? That's 3 - 3 = 0 damage. You still hit, you just didn't hurt them.
This means your high rolls matter in combat the same way they do in other RPGs. That dopamine hit when you roll a 9 or 10? You get it. But now it's tied directly to the damage you inflict, not whether you connect at all.
The Cinematic Payoff
This system creates moments that feel like action movies. Your character is cornered, down to 8 Luck Points, facing three enemies. You roll a 2 on your Brains Check to remember the building's layout. You spend 2 Luck Points to guarantee success. Then you attack with your shotgun, roll a 10, and drop one enemy for 9 damage. Your second attack rolls a 7 for 6 damage. Another one down.
For the last year or so, we've been giving our ruleset a much-needed root canal. What started as a relatively simple ruleset has grown with each module we've published, and to keep growing, we've had to prune it to keep it true to its origins.
Let's start with the big one: Luck Points.
Three Jobs, One Resource
In most RPGs, you've got hit points for survivability, some kind of meta-currency (inspiration, fate points, bennies) for rerolls or special abilities, and maybe a separate magic system with spell slots or mana. Three different resources doing three different jobs.
321RPG collapses all of that into a single resource: Luck Points.
Your Luck Points serve as:
Hit Points - Your health and survivability
Push Your Luck - Spend them to adjust stat rolls (1 LP = -1 to your roll)
Magic Fuel - Casting spells costs Luck Points
This creates a tension that runs through every session.
Do you spend 3 Luck Points to guarantee that crucial Brains Check to defuse the bomb? Or do you save them in case you take a hit in the next room? Can you afford to cast Fireball when you're already down to 15 LP and there's still half a dungeon ahead?
Starting Luck
At character creation, you get 20 + 1d10 Luck Points. That's your baseline, but it's not your ceiling. You can gain more through healing, clever roleplay rewards from the GR, special items (lucky baseball cards, Castlevania-style chicken hidden in the wall), and end-of-episode bonuses. There's no cap.
When Your Luck Runs Out
Hit zero Luck Points? That's it. Character death is permanent in 321RPG because the game is designed for 3-8 session story arcs, not multi-year campaigns. You're not losing a 2-year investment. You're creating a powerful story moment where that death actually means something.
This isn't about being cruel to players. It's about making every choice matter. When you spend those Luck Points, you're gambling with your character's life. When you save someone else by taking a hit for them, it costs you something real. When you go down swinging, it's dramatic because the stakes were always genuine.
And when you're down to your last few Luck Points and pull off that impossible shot or heroic leap? That's the cinematic moment we're chasing: the hero reaching way down deep to accomplish something that seems to come from nowhere.
The Heroic Sacrifice
There's one more thing Luck Points can do: you can spend all your remaining LP in one final act to save your allies. Dive on the grenade. Hold back the demon while your friends escape. Draw all the enemy fire so the team can complete the mission. It costs your character their life, but it could turn the tide. The GR decides exactly how the scene plays out, but your character goes out the way heroes should: making their last moments count.
We’ll be back with more soon. This book is really shaping up into something special that we can be proud of. Even better, it is going to be fun as hell to play.
Stay safe out there, and may the dice always roll in your favor.
We are on our third pass, bulking some bits up while slimming down some others. We've been trying to simplify some of the language as well. While a Rule Book is, in a lot of ways, an educational tool, the goal should always be that it is easy to read and enjoy.
This one is feeling really good. I am truly confident that it will be a pick-up and play experience.
Later this week, we'll be sending the Expanded Rule Book (which I think will ultimately be called 321RPG Core Rule Bookupon release) to some of my favorite creators and pals for a peer review.
I'll have more on that in January.
All the best to you and your families during the upcoming holiday season.
Stay safe out there, and may the dice always roll in your favor.
We have been working on getting the rule book right and, as a result, have torn it down to the studs. We knew going in it wasn’t just going to be a new coat of paint and a repackage; we wanted to deliver the definitive rule book for 321RPG.
So now it is triple the size.
Rule Book Manuscript
And that is without the full-length adventure, which we are also currently tweaking. So this is really exciting for us.
What is also really cool is that, while this system was created five years ago, it is now truly informed by five years of playing the game. It is rad to see it torn apart and see what we had dialed in from the start, but also what we missed the mark on.
Believe me when I say we found something we overlooked in rolling basic checks that was so mundanely obvious that I am gobsmacked it wasn’t included in the first place.
This book will consist of the rules that worked from the beginning, things learned and perfected through play, and some new stuff that will knock your socks off.
In other news, Ham & Egg Publishing has a cool new project happening that I would love you to check out.
Cover by Sally Cantirino
We were asked by the creator of Sickest Witch, Justin Sirois of Severed Books, to create the first 3PP adventure for Sickest Witch. So we are stoked to launch Under the Shadow of the Noon-Day Witch on Kickstarter. Here is the synopsis.
Under the Shadow of the Noon-Day Witch: or, A Treatise Concerning the Nature of the Alliances of Witches; Being Admonitions to Lords, Counts, Barons, Witch-Hunters, and All Men of Authority, Touching the Folly and Peril of Attempting to Deceive or Entrap a Coven comes from Ham & Eggs Publishing, the creators of the 321RPG system. It’s the newest third-party adventure for Sickest Witch RPG. Run using the Severed System, this standalone tale brims with political intrigue, fire and brimstone, and the brutal machinery of medieval torture, all driven by Purity Rose in their crusade to cleanse the world of witches.
Under the Shadow of the Noon-Day Witchis live now on Kickstarter, and you can check it out at the link below.
First up, I blinked, and it is September! My apologies for missing the August update.
In project-related news, I am wrangling the guest writers for the zine and fine-tuning the adventure included in the book.
It honestly feels good to go back to one that you poured so much into and make some of the “Ah, shit” tweaks after the fact.
Mind you, I’m not talking about going in “Full Lucas” and Greedo shooting first. But man, there are some points after a project is complete that you go, “Ah, shit,” that could have been slightly better.
Let's call it a wee touch-up.
That’s it for now. I will definitely be back in October, because, unlike August, October is my favorite month, and I won't let it slip through my fingers.
Stay safe out there, and may the dice always roll in your favor.
