Weather Generation 1: What I Want in a Weather System

At this blog, we are interested in practical simulationism: rules that get us close enough to reality while maintaining usability at the table.

Weather generation is great for this because:
        -We have tons of weather data for many locations in the world
        -It’s a background system that any RPG could care about
         -It feels solvable—there is a best way to do it

The goal of this series is to see if we can come up with a general purpose rule to go from real-world weather data to a working weather table. My criteria are:

        -It has to be simulationist. That means it has to ‘match’ real world weather data from a particular place. How close does the match have to be? We’ll learn more about that as we go through this series.
         -It has to be algorithmic. There are tons of cool ideas at there for generating weather in this or that environment. But they can be hard to use because the descriptions are generic. E.g., “Fall weather”, or “Tundra weather table”. It’s much easier as the GM to say: “this environment is like Egypt. Let me use an Egyptian weather table”.
        -It has to be practical. There is a level of taste here. You can create detailed, and probably more accurate, weather if you’ve got a dozen tables and after four rolls you learn that you roll 2d6+2 on subtable C. But this is not useable at the table. I prefer a strict boundary: no more than two rolls, and no more than two tables. A d100 table is two rolls (2d10) and one table—we aren’t going to go much beyond that.

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So what options are out there for us? First, there are tons of variations on table-based methods. Here is a selection:

(1) Roll on a single table. This is the most popular. I like this version for 5e; here is their table for spring:  

 

(2) Movement along a table. This is how the Wilderness Survival Guide does it: it sets a range of reasonable temperatures based on environment, then rolls a 2d6 each day to change. If there is a chance of precipitation, you roll on a separate precipitation table (again based on environment).

 

(3) Multiple tables with jumps. Here for example, you have two tables (basically ‘nice weather’ and ‘bad weather’). Each day you have a 75% to stay on the same table and a 25% chance to jump tables. This adds a bit of constancy.

(4) Independent tables for temperature, precipitation, etc. There is an in-depth version in Dragon #137, by Lisa Cabala, that perhaps gives the apotheosis of this approach. Here is Table 14, for Polar Temperatures. 

 

        (5) There are also souped-up versions of these which I’d call ‘computer-assisted’ tables. Here is a post corresponding to this spreadsheet. I’ll be honest, I don’t really follow it, but I see they have little dials like a “rain multiplier of 0.8” in early summer. 

Beyond tables, there are there two other systems I’ve seen that are worth mentioning.

(6)  Take a real place, pick a year/time that corresponds to your campaign, then pull weather from a database. I see some people recommend the wundergound database. The idea is, you pick a location corresponding to your desired weather, you pick a year, and then use the day-by-day weather. So maybe my campaign starts on September 7 of DR 1000 (or whatever fantasy system I want). I decide the weather is like Chicago. I pick 1955, arbitrarily. Then the weather on day 1 of my campaign is like September 7, 1955 in Chicago. And I progress day-by-day.

       (7)  Use a hexflower, a hextable with structure to it, where you will move from cell to cell based on a roll. Here is an example. If you go off grid then you loop around, unless you hit an X. These are aesthetically pleasing and have some memory effects to them. 

 

      So much for the survey. Where do these techniques land from the standpoint of practical simulation?

      First, computer-aided methods are a no go. If you use a computer already maybe it is not that big an ask. But if you don’t, having to start bringing your computer to games, and possibly configuring internet access, just to get weather is not going to happen.

      Second, we should be wary of tables that get too complicated. The Wilderness Survival Guide and Dragon #137 were both comprehensive because they considered a wide variety of possibilities (like ‘Arctic’ --> ‘Hills’ --> ‘Spring’). This is probably good from a simulationist perspective, but it means flipping pages at the table. (I’ve seen this complaint elsewhere).

      Third, I’d like to quantify how well it matches real weather. This is my biggest source of hesitation with the tables I’ve seen—I can tell the authors have put a lot of thought into their tables, and making them realistic, but I haven’t seen any data in that regard. (Of course doing so would have been way more difficult in the 1980s).

      The third point matters because real locations are how we’re going to orient ourselves with respect to the weather. I want to be able to tell the players “we’re in the Moonsea, so the climate is like Chicago”. That immediately grounds them. Many of the systems seem to use a more vibe based approach—we want there to be more predictability, so we added a mechanic for that.

      It may turn out that simulationism clashes with gamism and using real weather tables means weather that is too constant or too unpredictable or too slow to change or whatever. That’s all well and good—but I’d like to see some proof of that first, which we can only get by comparing to historical data.

Adventure Review: Lost Citadel of the Scarlet Minotaur (Levels 1-3)

 

Adventure Review: Lost Citadel of the Scarlet Minotaur

Shadowdark RPG. Levels 1-3. My experience: Run 2x for public games.

A tight dungeon crawl with room for things to go sideways.

This is the starter mod for Shadowdark RPG, and it comes freely available in the quickstart set. The quickstart set comes with level 1 pregens so it will be fast to get up and running.

I ran this adventure publicly twice, both with three person groups.  

I love the concept and theming. Kelsey based it on the ruins of Knossos on Crete—the original inspiration for the Minotaur myth—and it’s a cool labyrinthine complex. It's what you'd call a "xandered" dungeon, meaning there are multiple entrances and a lot of interconnections within a single level. There are multiple factions—Ettercaps and Beastment—that the players can interact with. They have their own goals and aren't just there to fight, so there's room for negotiation or conflict. The Ettercaps want treasure, which puts them into conflict with the PCs, but can also be a common goal and cause them to become allies. The Beastmen mostly want to hide but have access to secret tunnels that give the players more ways to navigate the dungeon. All of this is great design.

Then there is the minotaur. At a Level 7 creature, it is strong enough to kill or even TPK the party. And, they are bound to encounter it, because it becomes more likely every time they get a random encounter. That gives a fun sense of looming danger. When my players encountered it they ran and we had exciting chases through unexplored areas. You may want to exercise judgement regarding the danger level you want. When the players encounter the minotaur, if it wins initiative and rolls well it can kill someone without them getting a chance to respond. Or you could have it spend a turn bellowing and set off a chase sequence. If you do a chase, they can lose it by staying out of sight for 1d6 rounds, which is a fun dynamic. Its way better than a static boss.

At the same time it is weak enough that the players can overcome it. In one session they got it with help from the Ettercaps—they encountered it as they were leaving the Ettercap lair, having made a deal to join forces to acquire a magic sword. The Ettercaps webs locked it in place and the players hacked it to pieces.

Because there are multiple entrances and factions, every party will have a different experience. I could imagine things going south pretty quickly for an inexperienced party, though. In fact, the very first room on that route has an Ettercap that tries to escape and set up an ambush. If they do, the Ettercaps are strong enough that they can TPK a 1st level party. If the players aren’t careful that could happen fast. My more experienced group scouted the hidden entrances first, checked out the courtyard from above, and had a lot of strategic options. Player skill matters.

All of this is good stuff. One thing I would have liked: one group did a perimeter sweep and asked for the dimensions of the structure from the outside, and there wasn’t much to help from the mod. The labyrinth section isn’t clear about where the tunnel starts on the outside or how it transitions to the inside. In general I never got which parts of the dungeon were underground/above ground, and some artwork of an exterior view, or just some more dimensions, would have helped. I felt bad that I couldn’t give the players a better description there.

Regarding running time, I had a 3 and a 4 hour session and both worked, exploring maybe 50-60% of the dungeon. That was enough time for them to try out multiple entrances and get some of the passageways from the different entrances to line up and match with each other, which was satisfying. It felt like they were learning about this place. It works well as a one-shot even though there is more content than you can complete in a one-shot. 

I had the players map it out themselves which I recommend. It is challenging enough to be fun, and not so hard that they will get hopelessly lost. I had an experienced and an inexperienced mapper and both did fine.  

It is also easy to run as a DM. I spent maybe 30 minutes to an hour reading it and was ready to go. That said it could have done more to set up the motivation. There are these three old kings, each with a powerful magic items (sword, spear, greataxe) present which are a fun goal, kind of like White Plume Mountain, but the players won’t know if they don’t get it on the rumor table. I’d just give them that by default to give them a mission. It would be nice if the mod had listed where each one was up front. 

One final comment: the pregens you get from the quickstart guide seem much stronger, in terms of statline and HP rolls, than you would get with rolled characters. I would use the pregens, or it could be a very difficult mod. 

Overall, running this mod has increased my opinion of Shadowdark. I had run some of the overland content from Cursed Scroll #1 and it didn't work for me. The minimalist approach didn't translate as well to the hexcrawl and I felt like as the GM I had to bring a lot of my own ideas to make it work. But it is much better as a dungeon crawl and I hope to try more of those.

Expedition D&D Dev Log Part 2: Basic Expedition Rules

In the second post, I want to dive into the details of the expedition system itself. Following on the Source of the Nile rules, I want to have two base units you can hire: soldiers and bearers.

Soldiers are going to be pretty much the same by default. I’m thinking of the DCC retainers, maybe amping them up a bit because Simple D&D has higher HP. So I’ll set them at 4 HP, +0 to hit, and dealing damage by weapon (typically d6).  Their armor class is set by whatever armor they wear, and they have zero bonuses to their stats—generic mook-type characters.

Bearers, on the other hand, have no combat abilities at all. If a fight breaks out, they’ll run, scatter, or hide.

Next, I want to establish some carrying capacity limits. I love the way Source of the Nile handles this. Each bearer can carry about 10 units of supplies. Bearers don’t have weapons or armor, so they can always use their full carrying capacity for supplies.

For the soldiers, we’ll make a tradeoff. They will also have a base capacity of 10 units, but their weapons, armor, and other gear will count against that total. If you want to bring along a lot of supplies, you’ll need more bearers, because your soldiers will be partially loaded down with their own equipment.

For the heroes, I’m considering tying their carrying capacity to their strength score, like in Shadowdark. But I’ll put a pin in that for now.

Next, let’s get some numbers for food. Regarding food, I found a few sources from the Roman army; one says between 59 and 78 lb per man per month, while another gives 2.5-2.8 lb/day. I’m going to assume this didn’t change much. As our baseline for supply I’ll approximate 10 units ≈ 100 lb, so we’re at something like 1-2 units of food per unit per week. I decided to keep it simple at 1. Maybe this is generous to our expeditions, but I like how easy it will work in game.

For water, the sources say anywhere from 2-12 L/day (depending on conditions). The daily ration in WWI was 4.54 L/day, Vietnam was 3-5 L/day, but could go to 10 for certain duties. With 1L = 2.2 lb, that is something from 4-10 lbs daily. We’ll be generous again so that our expeditions can stay in the field longer, and say 1 unit of water daily per two individuals. But, we’ll give this multipliers, noting that multipliers up to 8x are historically plausible. Maybe we’ll have some rules to apply these in hot environments.

Finally, I want to make some other decisions about water. First, I don’t want to track containers. Caravaneer did this, and it worked only ok because it was a video game and I can’t imagine doing it by hand. Second, I don’t want to track it while you are along a water source. I like the idea of what this system will do for water tracking. It will be really demanding in terms of weight to carry water, so it will be hard to move away from water supplies. I like that idea and I’m excited to see it play out.

So there are our working Rules:

Bearers: Do not fight. Carrying capacity of 10
Soldiers: HP 4, AC and attacks as equipment (+0 to hit). Carrying capacity of 10.
Food: Each unit eats 1 unit/week
Water: Every two units consumes 1/day. Subject to multipliers of up to 8x according to condition. Do not need to carry if next to fresh water supply.

Development Log: Expedition D&D (Part 1)

 I'm going to start blogging about the OSR system I'm creating, which I'm calling "Expedition D&D". 

My goal looks back at the long history of adventure storytelling—a genre that stretches all the way back to some of the earliest recorded stories like the Epic of Gilgamesh or the Odyssey. Over time, that tradition evolved through tales like Beowulf or the Arabian Nights. It came to America with Last of the Mohicans and then the pulp fantasy of the 1920s and ’30s, with authors like Robert E. Howard and H.P. Lovecraft. And you can trace that DNA right up to modern adventure films like Indiana Jones or The Mummy.

This kind of adventure storytelling leads directly to what folks like Ben Milton call “adventure gaming”. I love that term because it places these games in the context of that literature and history. The adventure is the heart of Dungeons & Dragons. 

Modern D&D usually focuses on a small cast of characters, one for each player. Each one of these is a hero in their own right. It's like a Mission Impossible team where everyone crucial to the mission.

But the scope of adventure storytelling permits larger parties, which I'll call "expeditions". Think back to the Odyssey: it isn't just Odysseus alone, but Odysseus and his group of soldiers. I also like Michael Crichton's Congo, or Lovecraft's At the Mountains of Madness, or the historic Lewis and Clark expedition (the pair had some 40 people in support). 

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To make this work, I want a system that supports three types of play. The first is expedition play, which is your overland travel. You're controlling heroes, but also a number of generic soldiers or porters, some perhaps with special abilities, who are part of the journey. Here you'll do hex-crawling: you’re exploring new places, dealing with hazards, managing the morale of your team, ensuring everyone’s fed, and keeping track of resources.

Then there’s the hero play, your classic dungeon crawling. Those smaller scale adventures where the heroes are engaging in combat or exploration within a defined location.

Then, I want to have some support for mass battle play. If you have an expedition with 50 or 100 guys, you might end up in a large combat and the hero play rules won't work. 

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The simplest part is the mass battle element. For that, I’ll basically start off using the old Chainmail rules. If that ends up being a problem or not fitting perfectly, I’ll adjust from there.

For the hero play, there are a lot of great systems out there—OSR games, Shadowdark, and so on—but I’m going to use one called Simple D&D. It’s something I got from a friend named José. Characters start out strong enough to feel heroic, rather than super fragile at level one, and the progression slows down around level three. That means the heroes can become useful and powerful, but they won’t overshadow the rest of the expedition. They’ll still need to rely on their team and resources.

As for the expedition system itself, I have the least experience there. I'm going to start with the Source of the Nile rules. I actually played that game with one of the original creators, Ross Maker, who was part of the Blackmoor crew. David Wesley was the co-designer, so it has a nice link to RPGs. Source of the Nile is very expedition-focused—you have a hero, some soldiers, bearers, you track food and deal with environmental hazards—and I’ll be building on that as the expedition framework.

 

Adventure Review: DCC Convention Module 2019: The Inn at 5 Points (Level 2)

                  

It's a decent convention mod, but there are many better ones in the Goodman Games catalogue. 

The Inn at 5 Points suffers from a lack of direction & a way for players to learn the lore. The first half of the adventure is the journey to 5 points; there's a nice in medias res start battling the beast on the cover (the Wolf Wyrm), a flashback to meet a guy whose party was killed by said Wyrm, then a flash-forward to the combat. The guy tells you someone at the inn has a treasure map for sale, so you head to the titular inn and have a bit of roleplaying. Then in a twist that's in no way foreshadowed, a rat cult completes their ritual, the inn sinks into a massive crevasse, and the players have to defeat the cult.

The individual pieces work. The Wolf-Wyrm is a fun fight, the roleplaying has enough for players to grasp onto, there's a nice place for a break after the inn falls, and the last fight is enjoyable. But it's incoherent as a mod. The rat people are part of a lawful cult that wants to destroy the Inn because the Inn has a reputation for neutrality. But this lore isn't manifested in the plot; you have to use some of the NPCs to give an infodump, otherwise the players will be last. The Wolf-Wyrm isn't connected to the cult at all. At most, it causes the ground to shake when approach, and later shaking in the inn (right before it drops into the crevasse) will be interpreted as a second one approaching. 

There's no real inciting moment or goal. The convention mods that really work (Tower of the Black Pearl, Frozen in Time) start with something for the players to do--a ruin to plunder, a captive to save. In this, you're just wandering through the woods, you get a vague hook (head to the inn to get a map), and the players go along for the ride because they're good sports and get that this is a con game. 

The crevasse itself basically has one big boss fight and some side passages to explore. But in my experience, once the boss fight is over the mod effectively is and I describe the remaining rooms as part of the denouement. 

I made one big change: the guy you meet at the start (Dolmand Frey) wanted to join the party and get the treasure map, giving the players more of a connection to the plot and a possible backup PC. I had them run him as a retainer (level 0) unless someone died, in which case they'd run him as a level 2 warrior. I also made it so he didn't know the contact personally, so the players got to take the lead. 

This took about 3 hours to run, about 90 minutes to get to the inn falling and another 90 for the cavern.

This is $6.99 at the Goodman Games website.

My Experience: I ran this for one con game and for one game with my regular group.

Link: https://goodman-games.com/store/product/dcc-convention-module-2019-the-inn-at-five-points-pdf/

Price: $6.99 (PDF)

Adventure Review: DCC Free RPG Day 2021, Tomb of the Savage Kings (Level 2)

 

 

A decent adventure for a one-shot, but doesn't live up to its title. 

There's a trio of "savage kings" mods put out by Goodman, starting with DCC #17: Legacy of the Savage Kings and continuing in DCC #66.5: Doom of the Savage Kings. Both of those mods are excellent, and the marketing in Tomb suggests more of the same. 

Unfortunately, the connection ends at the title. The previous two mods take place in temperate areas, swamps, fens, and forests, while Tomb transports the action to an Egyptian themed setting. It's a homage to the many Mummy movies, and gets the adventurers in as rescuers of a kidnapped heiress.

The lack of connection to the other Savage Kings mods makes it an awkward fit for campaign play. I bought it thinking I could link the three, but it didn't make sense to drop Tomb into my setting. It isn't a big deal, as the lore is pretty minor anyway. A shame. A mod with this title should naturally fit after DCC #66.5. (You could use this and not DCC #66.5 in your campaign, but the other mod is superior). It also includes some game breaking elements (like PCs being lost in the past permanently) that don't work that well for campaign play.

It's more serviceable as a one-shot--the players get the hook, and they're off for the tomb. There's a bit of intrigue; they're hired by Zita to find her sister, Isobel, who joined an adventurer named Ardeth in robbing the tomb. But the story isn't quite true: Ardeth doesn't exist, and Isobel was actually kidnapped by the mummy awakened by Zita's own tomb-robbing. Zita can't deal with it, so wants the PCs to help. 

The players have a chance to learn this backstory through a halfling companion, Wemble, who helped Zita's original mission and joins them on the trip. There are some clues to suggest Wemble isn't being forthright. But in my experience, it's easy for him to fade into the background and the PCs to not pick up on any of it. Even if they do, not much changes. It feels more intrigue for the sake of intrigue rather than something gameable. 

The tomb itself is solid, although I would have liked to have more combats early on. The combats are very easy until the final boss encounter, which is hard and will take a while. I don't like that for a one-shot, because then the players don't have the best grasp of their abilities going into the finale. 

It also gets negative marks for useability. When they enter the main hall, there are these panels with a bunch of pictures and hieroglyphs. They decipher the pictures, read the hieroglyphs, and learn the Tomb's history.  There's a nice picture of the walls in the book, but no handout. And it's spread over two pages and very printer unfriendly. I ended up combining the walls and inverting the colors manually to end up with something serviceable. The Judge will also want to print out the text of the hieroglyphs as a handout. If you don't, the PCs are relying on your (much less fun) descriptions, and there's a lot of information, so you'll end up describing it multiple times...

This adventure really needs a rival adventuring party, who knows about Whemble and can reveal that intrigue, robbing the tomb for their own purposes. Think "The Mummy (1999)" with Whemble cast as Beni. It would add some more roleplaying and combat opportunities. 

This took three hours for me to run; 2 for the main tomb, and 1 for the final combat.

This is $6.99 at the Goodman Games website.

My Experience: I ran this for one con game.

Link: https://goodman-games.com/store/product/dcc-rpg-tomb-of-the-savage-kings-free-rpg-day-2021-pdf/

Price: $6.99 (PDF)

Adventure Review: DCC #79.5, Tower of the Black Pearl (Level 1)

Tower of the Black Pearl is one of the best starter DCC mods. Pick this up if you're introducing players to the system or want to run a public game, like at a convention. 

I'll start with the premise: there's this tower far off-shore, which is only accessible one night every 10 years, and that night is tonight! There's a pearl of great value inside, but other pirates are on the hunt. The players make their way out there, then have to deal with a series of challenges: the pirates (combat or roleplaying) and some puzzles (a rotten staircase, a trapped room which will flood and drown you all). They'll finally make it to the room with the pearl where they extract it...flooding the entire tower behind them and forcing them to race to the surface. 

Then, the usability: it's very easy to pick up and play--the entire thing is about 20 pages, including art and handouts, and in a large size font. That helps the GM scan at the table. The whole thing takes ~20 minutes to read through. And it's fairly linear, so you can do a good job from a single read through. It'll have a similar length each time you run it; in my experience, 3-4 hours. You'll have no trouble getting this to the table. 

Then, as an introduction to the DCC system: it starts with an easy combat encounter (all starter mods should do this!) so the players have a chance to acclimate themselves and learn how their characters work before making consequential decisions. There's a nice mix of combat, puzzles, and roleplaying. The players will need creative solutions to the puzzles at the end (how to get the pearl from all the snakes?) and have important choices to make along the way (backstab the pirates, or side with them?). I'm not sure it would do well as part of a campaign. The candles, which provide a way to snuff out every lawful hero in existence, have too much potential to derail things. But it's fantastic as a one shot.

New DMs, be advised: the biggest challenge is not the pirates, and not the water trap--it's those damn stairs. Most everyone tries to make the jump, most everyone falls, and then ends up with broken bones or dead characters. 

This is $6.99 at the Goodman Games website.

My Experience: I ran this for several convention games.

Link: https://goodman-games.com/store/product/dungeon-crawl-classics-79-5-tower-of-the-black-pearl-pdf/

Price: $6.99 (PDF)