Roomless, Mapless, Distanceless - a micro-ruleset for dungeoneering

I am currently running a heavily homebrewed game of Ultraviolet Grasslands with heavily homebrewed rules. Ultraviolet Grasslands, for those not in the know, is Luka Rejec's imminently-to-be-released masterpiece of 'steppe-crawling' goodness.

The setting and rules are phenomenal at simulating looong periods of time over looong distances, tracking your party as they make pilgrimage through a psychedelic landscape over multiple timezones. Along the way you might come across Discoveries - strange ruins or settlements of the long-ago forgotten times potentially brimming with treasure and technology.

One small trade-off is the rules don't really help with smaller distances and times like meters and minutes pottering around a dungeon.

You could just use rules from D&D or another system, but you risk making the game too nitty-gritty and dungeon-centric, and soon you've forgotten about the wild, wide steppe and you're spending eight consecutive sessions hauling gold pieces out of a three-level crypt, tapping every brick with a 10' pole. That's not UVG.

I need something that gets the party in and out in two sessions or less and boils down to the most flavourful, interesting parts of the dungeon. Just like how UVG boils away weeks of endless prairie down to the interesting parts of starvation, predation, and exploration. So I asked for ideas over on the UVG Discord and built something out of what was suggested.

Dungeon Areas

A dungeon is broken into thematic areas instead of specific rooms, corridors etc. If it's really important for whatever reason, you can specify that Area 3 can only be reached through Area 2, but broadly I won't be paying attention to how the spaces connect. 

The way I plan to use this is have the areas be encountered broadly in the order I write them. This means I can invent the dungeon on the fly, coming up with a few starter areas and having time to think up later areas mid-session while the starting areas distract the players. 

1. Dusty turbine hall
2. Haunted control room
3. Oil-flooded service tunnels
4. Golem hangar
5. Lipid clone vats
6. Overgrown xenoherbarium 
7. Necronuclear anti-core 

Exploring an area takes an Hour. In fact, most interesting actions take an Hour. Unless it's really obviously a short activity, always err on the side of making things last an Hour.

By "exploring" we assume the players, like in Fallout or Skyrim, creeps around half-crouched in the dark for ages, tentatively poking their heads around corners and looking in random rusty filing cabinets or anything vaguely eye-catching until they loop around on themselves and have a good understanding of the topography of the space.

At this point you should let them know about anything especially interesting. Maybe have a few bullet points next to each area

1. Dusty turbine hall
• A giant wall of huge, chunky breaker switches (will turn on noisy turbines, air conditioning, and facility lighting)
2. Haunted control room
• A big, tantalising safe door in the far wall
• The souls of the control crew, convinced they can still avert the long-since-happened disaster (will either think you are extra crew come to help, or the saboteurs responsible)

This isn't essential. Again, only write details if you're struck with inspiration. Or ask the players what they see. If you're already being fast and loose with details, no harm in letting players add to the brainstorm. 

Optional Rule: Number the areas in a list and roll a d6 every time they press deeper. If you have more than 6 areas, you count up from 1 and skip any already explored (so if you've been to Area 3 and roll a 6 you go 1, 2, 4, 5, 6, 7) so higher areas are necessarily deeper inside and impossible to reach immediately.

Alarm Dice & Encounters

By doing certain things you accrue Alarm Dice (a d6). These represent how the dungeon is waking up, and reacting to, your presence. You gain Alarm Dice by

1. Exploring an area
2. Having a violent and/or loud encounter
3. Making very loud sounds
4. Activating machinery/turning on the power/pushing the big red button/whatever
5. Whatever unique to this dungeon you think warrants raising the stakes (e.g. grabbing the golden idol off the plinth) 

Like I mentioned earlier most things take an Hour. Every Hour prompts an encounter check against the Alarm Dice. Things that take an Hour include

1. Exploring an area
2. Hacking apart overlarge treasure into managable chunks
3. Resting, dawdling, or anything you as GM think appropriate as wasting or taking up time

(notice exploring an area gains an Alarm Dice and prompts a check against said Alarm Dice. Always add the Alarm Dice before checking)

You check for encounters against Alarm Dice by rolling all of your accumulated Alarm Dice and looking at the results and comparing against your Encounter and Treasure tables.

• The number of rolled 1s correlates to your table of Encounters (i.e. rolling 3 1s means you encounter item no. 3 on your list of encounters)
• The number of rolled 6s correlates to your table of Treasures (i.e. same as encounters - rolling 4 6s means you find item no. 4 on your list of treasures)

Thus you will not encounter or discover encounters and treasures higher on their lists until you have spent longer in the dungeon. For encounters this means they should represent the inhabitants of the dungeon becoming steadily more aware of and (probably) more hostile to your presence. 

1. Goblin sentry, dozing

2. Gremlin teamsters, off-duty

3. Goblin patrol, nervy

4. Hobgoblin lieutenant, suspicious

5. Goblin flying squadron, trigger-happy

6. Hobgoblin stormtroopers, outraged

You could have a 0th entry for some thematic environmental effect if no 1s are rolled. Perhaps lava, or your torches die, or a haunting voice says something cryptic about the fate of this long-forgotten place, or you spot a security camera looking at you.

So in this example, the party encounters Encounter #1 and Treasure #1. Perhaps the monster has the treasure on their person, or perhaps they're guarding it?

Optional Rule: Write a dungeon-wide reaction table staggered by accumulated Alarm dice. You can assign more than just attitude to the table e.g. number of monsters, how aware they are of your presence etc. 

1-2 Alarm Dice (AD): torpid/surprised/alone

3-4 AD: curious/"what was that?"/pair or trio

5-6 AD: concerned/"who goes there!?"/squad of 5

7-8 AD: excited/"spread out, find them!"/2 squads and a leader

9+ AD: panicked/shooting at shadows/3 squads and a boss

Optional Rule: You could use the other dice numbers to inform your decisions further. Perhaps the number of 2s represents how concentrated the poison gas is in your poison-gas-mine dungeon, or perhaps you map the number of enemies in an encounter to the number of rolled 4s (e.g. one 4 = 1 monster, four 4s = a group of monsters etc.) 

Benefits to this system

The longer the party explore, the more aggressive and concerted the response becomes, but the more riches they will potentially uncover. This encourages hit-and-run approaches to dungeoncrawling.

This system means you don't need to worry about writing up dungeons ahead of time (especially helpful in UVG where dungeons are optional side-locations players may or may not explore). All you need is 1 or 2 starting areas, 1 or 2 monsters, and 1 or 2 treasure ideas, and you can write the others on-the-fly.

The nature of the monster-to-alarm intensity correlation is that you could just have one type of monster of increasing hostility if you can't or don't want more types of enemy.

1. Gary, thought he heard a noise
2. Gary, tentatively looking for you
3. Gary, firmly asking you to leave
4. Gary, threatening to call the police
5. Gary, armed and dangerous
6. Gary, panicky with a grenade