The Brinemarch Hex Run

by Lavamuppet

The Brinemarch

Brinemarch is a low-fantasy ¹ hexcrawl ² setting for the fog-shrouded coast of the greened Antarctic coast. The Brinemarch region faces the Indian Ocean, located at 70°E latitude in the Mac. Robertson zone.

PREFACE

This is a record of a longer learning process. This blog documents the design values, goals, and choices behind The Brinemarch Hex Run for later reflection. I have drawn fantasy and RPG maps since childhood; this project is an opportunity to learn how to communicate dreams of adventure, danger, and exploration in a new medium. A current edition of the playable material will (eventually) be available at lavamuppet’s itch.io.

Contents

• Preface
• Design Jam
• Design Goals
• Flavor
• Player Assumptions
• Hexcrawling Rules
• Magic
• Next: Tiles

THE OSR ANTARCTICA DESIGN JAM

The Brinemarch Hex Run was created for the 2025 OSR Antarctica Design Jam as a survival-oriented hexcrawl in a low-fantasy setting. One of the key requirement of the jam was that entries use role-playing systems that are freely and publicly available.

The original goal was to contribute to the jam. This was accomplished in February 2026. The design goals I had were as follows:

Create:

1. 100 discoverable locations keyed to a map.

2. Signals for meaningful navigation choices.

3. Travel hazards

4. A set of rules-agnostic tools to assist whoever runs the game.

5. Sufficient lore to make a pitch for the table

As of May 2026. How do I feel about these goals?

1. 100 discoverable locations keyed.

Review: I did not complete the goal. The document I submitted (Larkshore Landing) has 18 keyed locations for one section of the map. The information density that I was aiming for was 3-6 keyed locations per tile. The map included 27 Tiles. On the other hand, my notes and non-submitted material far exceeds the goal. Next step: I plan to continue "publication" of the other keyed locations. As far as I know they can be added to the https://aaj-map.netlify.app/ in due time.

2. Signals for meaningful navigation choices.

Review: Developmentally, as a new designer, and a new project, I did as well as I knew how with this. I have not done play testing yet. This will be something I will want feedback on from people who have played hex crawls, or tried out the Brinemarch setting.

Next step: Play testing Larkshore Landing using Cairn 2e and OSE.

3. Travel hazards

Review: again, I did as well as I new how with this. I think I came up with some novel designs that I hope are attractive, playable and not burdensome.

Next step: I will want to continue developing the travel interface with Brinemarch. Canoes are a very important part of the setting.

4. A set of rules-agnostic tools to assist whoever runs the game.

Review: Tentative success. I recognize a system-agnostic setting is not a selling point. However I believe the system-agnosticism is a statement about the setting itself and how it relates to outsiders. I went with it after considering the the pros and cons of going with a specific system. The strongest contenders have been Cairn 2e, and Old School Essentials.

Cairn 1e is most in tune with the low-fantasy survival themes. Early feedback about this project implied that forcing Cairn 2e to work as a hex crawl might not work as well since it is optimized for point crawls. Regardless if this is mechanically true, it does sound like people who play Cairn 2e would not be attracted to a hexcrawl setting. This is a bit of a vanity, assuming I finish the project and anyone should want to read it, I think they would want it to be legible in a game format that means something to them. Also, Cairn 2e has an implied setting that overlaps but contradicts some of the assumptions about Brinemarch. I tried designing to keep these complimentary, there are some recognizable echoes, but Brinemarch is its own setting.

Old School Essentials is the version of OSR gaming that I most enjoy using and playing. It speaks to my tastes in writing, design and art, not that I emulate that, but it's my preference, so I wanted to create a setting that could be played in easily, while being a distinct setting.

NEXT: play test more. If a particular system meshes better with the Brinemarch I might start to rewrite and communicate for that system.

5. Sufficient lore to make a pitch for the table

Review: It's enough for me, and so far I've good feedback. I'm willing to pair it back, or add to it if needed.

Next step: avoid lore bloat, monitor and adjust as needed.

DESIGN GOALS OF THE BRINEMARCH RUN

Rather than follow a single TTRPG (Table Top Role Playing Game, vs video game RPG) ruleset, this setting is written in an OSR (Old School Revival) ³ system-agnostic style. It is also designed to work well-enough (read: fun-enough) with rules-light systems.

Knave, Cairn, Into the Odd, Basic Fantasy 4th ed, Old School Essentials, SRD, or similar frameworks.

Guidelines Which I will Inevitably Break

1. Don't name game mechanics.

2. Don't track conditions

3. Do use descriptive tags

4. Don't describe assumed consequences

5. Do describe breaking points

6. Do assume adjudication

DESIGN SUB-GOAL: USER ACCESSIBILITY

The formatting and structure has the following aims

1. minimize scrolling or page flipping, using inline information and foot notes.
2. support navigation using nested hierarchy of information
3. support readability with visual hierarchy and UX principles.
4. support aesthetics by using prose and pictures as landmarks.
5. commitment to feedback and revision for accessibility as the project proceeds This is being developed in public, with revisions informed by play, feedback, and further research. ⁴

These objectives apply first to analog, then digital copy, and then the needs of table top simulator contexts (Dec. 14, 2025).

THE REGION SIZE DESIGN PROBLEM

Brinemarch covers a relatively large region for a hex crawl ² (though it is average size for most of the Antarctica Jam claims), it is roughly the size of South Carolina (32,020 square miles with 30,061 sq. mi. of land).

The size provides: -wilderness survival tension

• weeks-long journey -weather gradients -room for geopolitical tension -support for megafauna and apex predators

Any document made separately from the https://itch.io/jam/antarctica-jam will be organized by chapters of either watersheds, terrain type, or by tile ⁵

The rough distribution of [tiles] looks like this roughly:

_ _ _ A. B. C. D. E. F.
_ _ G. H. I. J. K. L.
_ _ _M. N. O. P. Q. R.
_ _S. T. U. V. W. X.
Y. Z. A&. AA. AB.

Terrain

• Mountains: I, N, T, O, U
• Forests: A, B, C, G, H, I, M, N, O
• Some coniferous stands in H, N, O
• Arid Flats (Desert/Salt): Z, A&
• The rest is plains of various elevations.
• The outer coastline tiles include: F, L, R, X, W, V, U, A&, Z, Y

For reference:

DESIGN FLAVOR

Most of my experience in gaming, reading, and writing comes from European and North American fantasy traditions. Defaulting to those conventions is easy, and escaping them entirely is neither possible nor desirable. They provide a shared language and recognizable expectations at the table.

Nevertheless, there is no inherent reason a hexcrawl must reflect only the geography, ecology, or cultural baselines most familiar to the designer.

The aim is for Brinemarch to present an inhabited, reactive, and dangerous landscape shaped by its situation in the Southern Hemisphere.

ASSUMPTIONS FOR PLAYERS

The goal is to support hexcrawling in a landscape that routinely reconfigures roads and landmarks. Some characters may be familiar with the ways of the land, but most will not.

Player characters are assumed to be agents of an outside power, such as the Empire or its chartered Company, engaged in exploration, trade, or extraction. These agents will find the local situation incoherent and resistant. Characters with established relationships to the land will, in turn, find the Empire and the Company dangerous and hostile.

The guiding design principle is that there is always tension between what is expected and what emerges. How that tension is resolved is left to play.

The Brinemarch Run

Player Introduction

Setting Assumptions:

Brinemarch is set on the coast of a greened Antarctica,which means glaciers are gone; the weather is perpetually cloudy and misty, a storm may take shape without notice, or worse a malestrom returns unseasonably.

The local nations maintain wards that prevent the return of ancient princes of oppression.

World history follows an Iron Age empire with caravels and colonial outposts, gunpowder, clockwork devices, but not industrial steam power.

Such an empire will have built a castle on an island with a natural harbor here and uses it as a base to explore and exploit the Antarctic interior. The imperial bureaucrats will call it New Sanctuary City, sailors will call it Brinemarch Harbor. These outsiders wrestle for resources and land, and their recklessness will disturb ancient powers. The locals call them, the People of the Flag.

Hexcrawling Assumptions

• Reroll weather every hex entered.

• 1 encounter or event roll per hex traveled, or day at minimum.

• 1 “what’s here?” sentence per keyed hex

• Getting lost on a bad roll

BASELINE WEATHER PROCEEDURE

Roll 2d6, take the lower roll. Add Wind and Lightning to Doubles **1d6 | Brinemarch Weather **

| 1 | Clear Skies, full visibility. | 2 | Mist, visibility reduced to 1 hex
| 3 | Cold rain; waters rise (travel speed: 1/2 on land, 2x on river) | 4 | Heavy Rain, floods (can canoe anywhere) | 5 | Hail Storm
| 6 | Snow (arcane, rivers freeze for now) |

Magic

The greened Antarctica is not completely thawed. It remains only mostly thawed. Small glaciers and extensive permafrost cover the Northwest quarter of the map. Fantasy elements come from under the ice. The history of the elves and dwarves ends hundreds of thousands of years ago with the “Abominable Freeze ⁶ that pause terrestrial life in a global cryogenic sleep,

As the glaciers receded mortals woke up from the cryogenic sleep wake up cranky, confused, coughing, and poorly adapted to a new world. Most perished after only a few hours. With help, some have survived and their children continue on in specialized conditions. These are gnomes, goblins, orcs, elves, dwarves, a dragon or two, and other mythical beasts.

Notes to self

for revision: