My Own d20 Heartbreaker and Intro Dungeons


I'm in the midst of writing and playtesting my OSR hack of Pathfinder/3.5. It evolved from a combination of having a bunch of dyed-in-the-wool 3.P players who don't enjoy change along with introducing hundreds of new players over time. As much as the 3.P game has accumulated tons of cruft I genuinely do enjoy the d20 core rules and unified mechanic, it's both easy to teach and easy to run. If any of you are familiar with my One-Session Kits you'll know I have a standard printout single page of basic rules that I hand out to newbies or people unfamiliar with the system. It's been a huge success, and immediately grasping the basics has let me expand into the crunch very easily as we play:
All of this coincided with reading more other rulesets and experiencing more types of games. I was a player in a very successful West Marches campaign, amazingly successful with seven DMs and a hundred players. Despite all the fun and success, though, the West Marches kept running into the limitations of its chosen system, 5E. The OSR-adjacent assumptions of the WM hexcrawl mesh poorly with the giant puffy HP bags of heroism that are baseline 5th Edition PCs. I proposed to the lead DM that he should look into E6, the old D&D 3.X ruleset that capped character levels at level 6. He couldn't really change rules mid-game (again, this is a hundred people) but he's going to be using E8 for his next WM. He also strongly considered 5 Torches Deep, the OSRish hack of 5E that encourages simplicity, but in the end he just found it too big, the rulebook is a meaty chunk for a rule mod, it's hard to get players to read that much closely. I've done my own E6 or E8 Pathfinder games, it's fun, but players really do feel annoyed to hit the ceiling there.

Enter Pathfinding Light. Pared down to the bone, it plays extremely old-school. Rather than muck around with the huge 3.P class list I cut everything down to the basic NPC classes, which correspond pretty well to the OD&D core:
-Warrior (Fighting Mans)
-Expert (Skill Monkey thiefish)
-Adept (Magic-Users with Cure Spells)
-Aristocrat (Jack-of-all-trades)
-Commoner (Sucky scrubs)
I've also taken feats down to those most commonly used, races are the basic Elf/Dwarf/Human/Halfling, and magic item shops are gone. Coupled with gold=XP, playing the hack gives me the feeling I like and my playtesters have enjoyed it a lot. I already was running 3.P more old school than most, eschewing grids in many cases, making morale rolls for monsters, throwing out CR as a concept, with PFL it's been a breeze to run.

This isn't me advertising, though, this is me working out the project for the system book, which is ambitious as hell. I'm trying to make these goals:
-Twenty pages A5 (I want this to be reasonable to ask players/GMs to read).
-Contains all the rules needed to play the game.
-Readable both from cover-to-back and as a reference.
-Hyperlinked (in the PDF) to the d20SRD for rule references and more options as needed.
-A one-page dungeon that is (A) fun and (B) a good intro to the system. Figuring out this is going to be its own challenge for information density, mapping, presentation, and of course dungeon design.


So, goals for the introductory dungeon. I'm not going to be making a sort of hand-holding conversational teaching dungeon, I'm not Skerples or ArnoldK. The procedures for running the game are generously given three whole pages themselves in the GM section (designated by a black border for physical booklet). What I do want is a dungeon that is enjoyable to both run and play in, but one that also shows off what old school play means. Elements I'm wanting to see:
-Dynamic "factional" play with at least some negotiation possible.
-Nonlinear map, with elevation changes and loops to allow obstacle bypass.
-Traps, showing first obvious traps to be avoided then hidden traps to be dealt with.
-Secret doors, so first an open secret door, then others derivable via mapping, then another purely hidden.
-Treasure that is interesting, some hidden, others obvious but dangerous to retrieve.
-Fights/monsters that can be run away from.
This is a pretty big burden to place on a one-pager. I get a few bits of format relief; the little bestiary is going to be on the page opposite the dungeon, so stats are covered. I'm showing how all the basic building blocks work, so I'm not writing out new content on my little A5 page. Given the size, I'm not going to have to put in random encounters (although I might). Finally, it can be very focused and immediate, I'm going to let the players provide the motivation (a core tenant of my play).

Thus, the Door of the Old Men:
Map in pencil right now, I'll be doing it in pen with a 10'=1 square scale eventually rather than this current 5' scale. It's a dozen keyed areas, which is about the minimum size that allows for exploration. I've got a dynamic story to the dungeon, which means it's not something just stumbled on, but it lets me put everything in a sort of tippy balance point.

Basic story of the place is that the Spirit of the Mountain (a mother-lovin' Ancient Red Dragon) long ago used this place as his throne, attended by a cult of servitors. At the time of the Old Men's ascendance they attacked the throne, sealed the Spirit away behind a brass door, and appointed an undead Guardian to watch over the place. Now a cult devoted to the Spirit have broken into the mountain and managed to get wrecked by the Guardian, who stands guard on the pillar surrounded by a neigh-bottomless pit in front of the glowing brass door. This tableau is instantly visible to the players looking in from the landing area (entry). The players are just village locals:
So, situation instantly visible, but if they just charge forward they get hit by scorching rays from the Guardian, survivors open the door, see dragon sleeping on a pile of honey-colored bones clutching a skeleton with a clearly magical dagger in its ribcage, they wake dragon, dragon eats them. By going through the sides they'll discover cultists, treasures, skeletons fighting zombies (cult leader's vs. Guardian's), and passages that the dragon can't enter. The front entry, that landing, should be something which can be clearly caved in. It's a nice dynamic dungeon I think.

Next step here is playtesting the dungeon, I'll have a group for that on Friday. Really, a lot of the challenge isn't going to be this fairly simple dungeon, but how to convey it on a single sheet.


Should be playing D&D instead
In a way, you're tilting at windmills, but... I consider chopping 3.x down to its component molecules to be a worthy goal. I have run a Pathfinder E6 West Marches game, and even writing up challenges for 4th-level+ PF characters involves far too much mathematics for me to have any fun.

You may also want to take a look at this:

Melan's Sword & Magic rules, a stripped-down version of 3rd edition that removes feats, special cases and all the other stupid junk. I have started using them instead of PF and so far, so good. Skill rules are simple as hell and, hugely, the monster statblocks are really simple and can be done by eye, just like in 1e.


What is any bit of TTRPG design but tilting at windmills? My eventual plan is to publish my own West March with some 184 keyed hexes (already keyed) and a four-level kilodungeon (already mapped). I'm going to run it in PFL so I might as well have a booklet out beforehand.

Any critique of the map before the playtest I'll gladly field.


My my my, we just loooove to hear ourselves don't we?
I know you've got space concerns, but I assume the traps and secret doors will be of the anyone can find/disable them, interactive variety?

My Bulls Run stuff has been a sort of 3e agnostic with a CR 8 Monster Stat Block looking roughly like this:

Immature Bebelith: CR 8; HD 12; 102 hp; AC 21; Mv 40, Climb 20; Bite +13 to hit (1d6+1+Radiation), 2 Claws +13 to hit (2d4+1); DR 10/Good, +8 Stealth, Improved Grab, +23 Grapple, Rend Armour, Web; CE.
Rend Armour: If both claw attacks hit; Armour takes 4d4+2 dmg.
Radiation: 1d6 dmg chemical burn + DC (Avg)+1/rnd cumulative Con vs Radsickness*.
Web: 30’ Range, +11 Ranged Touch, DC (Avg), 12 hp).

I lost some formatting with the copy/paste, but they're pretty tight on the page even for high CR monsters. The idea behind this stat block was to make it possible to 'take it or leave it' with a minimum of fuss. The DM should have enough info here to wing it, or quickly convert it to his own liking. I havn't decided what to do about saves yet since they're different in every system.

I turned the DC's into "Easy-Impossible" instead of assigning numbers. I'm thinking about doing that for other things as well. It takes away accuracy and turns every target into a quantum-roll which I'm not sure how problematic that would be. Basically I'm saying every target number is scaled to the character's level, so if I say it's an (Easy) Climb roll in my 7th lvl adventure, than I don't care about the character's bonuses, I just expect him to roll 5+ on a d20. The bonuses get factored in in the case of an opposed roll, or a close or modified roll, or in the case of outrageously high or low bonuses. Like if I assign a (Very Hard) DC to a Knowledge check, but the character has a huge bonus due to min/maxing or a special item etc. I'd reduce the difficulty of the roll. The point is. Less dicking around with numbers. Pretty sure this can be applied to AC's or maybe even Saves...


Whoa, those statblocks are sprawling. The one-page representative Bestiary I'm going with is a lot tighter. The basic idea is to show some very common creature types and also to show how to modify them and add templates, it's very easy to change a wolf to a dog, a zombie to a Zombie Giant, or a Hill Giant to a Hill Giant Zombie.
I'm also going to be showing the Easy-to-Impossible DCs with examples in the GM section. Understanding the simple math core is a primary goal I have in the section; if you have a Hard climb with howling winds, that's DC22 (20 for hard, 2 for inclement circumstances). It's a very easy system to run with that understanding.

I'm extremely happy with the adventure playtest, by the way. Decently complex map for its size that I was able to convey to them theatre-of-mind. Good dynamic situations, lots of use for various traps. I'm pleased.


My my my, we just loooove to hear ourselves don't we?
Whoa, those statblocks are sprawling.
Whoa, look at that tiny Pit Fiend block! Or the Lich that just says "spells". Touché sir! :p You're sending the DM to the SRD with half of these monsters, which is cool. In my case I'm cribbing half my monsters out of the Tome of Horrors, so I had to jot down a quick summary of special abilities, and once I started doing it, I had to remain consistent. It's not so bad when it's formatted:
Pretty good for a CR8 Outsider, really. I'm trying to shorten it without shrinking down to the brevity of a one-page dungeon. I really loved the tactical pages in 'Fall of Whitecliff' which inspired me to attempt a similar thing with the Summer Palace in Bulls Run, but it sprawled into a 2-page spread and was a total mess. In the end I was forced to return to a more conventional format. I'm still trying to keep things tight so I can cram everything into one omnibus in the end which is why I'm super interested in what you're doing here.

The Saving Throw question could be solved by saying which attribute is the monster's Good save? Like "Sv: Con" would imply that Constitution-based saves are the creature's strong roll which combined with the monster's HD could be more easily carried backward to older editions, or even forward? I'm looking for ways to allow the GM to adjudicate on the fly basically. I think that's what you're doing too?

Here's the Summer Palace page for your personal amusement btw:



That density is just about at max, but I think it does work. I think you might have more success if you are able to break up your visual appearance a little bit. I like to break up keys alongside the maps, giving a little bit more visual flow usually helps. Some dynamic looks will help right there.

I intend to hyperlink literally everything in the pdf version of this to the SRD but I am actually playing with some tricks to allow me to cut down on the stat blocks. For example, in the page before this I build an example monster that happens to be a 12th level adept; all those conditions are going to be outlined in a previous page. Even things like saves I intend to show as the average and I'm going to tell the GM to pull up one and pull down another as makes sense, for example a giant will have a higher fortitude and a lower reflex.


Here's an example from my latest:
Having the maps scattered with the keys ends to break up things for the viewer when he's rapidly scanning the page. A lighter, loser font than Times New Roman can also help with the "text block of doom" thing, although keep it conservative.


My my my, we just loooove to hear ourselves don't we?
Having the maps scattered with the keys ends to break up things for the viewer when he's rapidly scanning the page.
Nice! It's hard to see now, but I had it laid out so there'd be words and a map on each side of a spread, with a clean line down the middle that wouldn't cut any critical drawings. Unfortunately, my writing ran long and I ended up with that second column on the right at which point everything doesn't fit on the page anymore and the page seam goes through the maps if I reduce it. I went back to Whitecliff yesterday and saw what you are talking about with the dynamic paragraph layout. Maybe I was further influenced by the one-pagers in Stonehell? I was really stuck on the idea of getting each of the mini-quests on their own spread, but I could see how I could break it down to separate levels and spread each over 3 or 4 pages this way. Anyway, I've done too much now in a multiple-page format. Can you believe I did that stupid spread up there in Photoshop? Not at all a word processing tool. I will not be repeating that mistake again lol!

for example a giant will have a higher fortitude and a lower reflex.
So something like: 'Sv: 4 (Con)' for a Hill Giant? (Damn, they have crappy saves!)


A first draft is complete:

I still have a lot of hyperlink work to do, and I'm trying to think of some informational shortcuts that help make the character sheet more obvious.
Right now I haven't done much with color. I'm thinking about lightly shading the sheet section by section to correspond with colors in the character creation section, so slightly blue for stats, slightly green for gear, slightly yellow for skills, slightly auburn for spells, etc. I'm extremely fond of this character sheet, I use it for my one-session kits, but playtesting with completely new players I've noticed a little confusion at times.

Any feedback on the 20-page core rulebook there would be appreciated. I'm not quite at Knave levels of simplicity, but I really am happy with how new players have taken to the system. @bryce0lynch I know you luv one-pagers but this dungeon might be better than your usual fare.
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My my my, we just loooove to hear ourselves don't we?
Pretty cool, but

Going with 3d6 stat rolls eh...

I get that you're trying to cram the spellcasting into one page, but I hate it. The spells per level graph is confusing and (once again, I get the layout and space concerns) I wish it was up with the character generation. This could maybe be solved by putting the Adept last and putting the spells immediately after?

Love the one-pager at the end!