Operating Weird Dungeon Machinery Considered Harmful

tsojcanth

March 7

Beautiful Yet Lost features, tuckered away in its ruins, sort-of-industrial, mostly broken down machinery. Maybe it's an automated pita maker. Maybe it's a vat that brews brews. Maybe it's a statue-replicator. Maybe it's an ornithopter.

Regardless: They often do not work perfectly. And, sometimes, fail catastrophically.

This is how I'm trying to handle them.

Machine Basics

Machines have mostly three things to them: purpose, power, and health.

The purpose is the reason of being for the machine: machine are built to make things, or do things on other things, or make things happen. For example:

a stone automated forge that makes axe-heads
an iron obelisk that recharges fire-magic items
a steel elephant walker, with a hut built on the howdah, and a hook on its tail, for wagon attachment
and so on

Power is what the machine needs to operate. For example:

mechanical power, for example a water wheel.
heat, for example a furnace.
star energy, for example a henge. Star power is always present, but henges are usually tuned to work at specific times with specific stars, so they supply power intermittently.

It goes without saying that you can use machines to power other machines, and engines are helpful because they convert energy to a different energy. For example:

a big coal-fire steam engine can power many smaller machines with either steam or mechanical power
a fire spirit bound into a demon-core (from mug-sized for a 1 hp Singe Sylph, to building-sized for a 24HD Fiery Flamingo) can provide both radiant heat and mechanical power via its crank shaft. And sometimes it cannot stop from providing both at the same time, together with pained screams, as the fire spirit it rages against the brass walls of its prison.

Devising application of harnessing other kind of spirits inside demon-cores is left as an exercise to the reader.

Health is how badly the machine is broken. From 6, perfect working order and totally fine, to 0, for when you do not even need to look at the machine to wanting to nope away. Health can be increased by 1 by skilled engineers spending 1d12 hours and some supplies, if they roll successfully (stat roll or skill roll or saving throw, depending on your game system and inclination).

As we are about to start having comedy health and safety accidents, machine health should not be quantified numerically, but should be strongly telegraphed to players, so that they know what is coming.

Machine Operations

First, the machine must be set up. Machines found after the catastrophe many machines are often already set up, as nobody has used them since the Catastrophe. However, as they have not been used since the Catastrophe, they might be clogged- and caked-up and might require set-up still (1-in-2 chance). If not set up, it usually takes a turn to set them to working order. Dials registered, regulators de-biased, cradles cleaned, pipes scrubbed, brass polished.

Second, the machine should be fed. Load ingots on anvils, hops in hoppers, fragrances in phials, whatever it needs. If might be far from straightforward for the PCs to understand what's going where, but rummaging in storage, nearby supply rooms, and a bit of common sense might help. Without the correct power the machine simply won't do anything, but if fed the wrong resources the outcome might be worse.

Third, the machine can finally be operated. Now, make a OPERATOR roll, and an BREAKDOWN roll. You want the OPERATOR roll to beat the BREAKDOWN roll.

The OPERATOR roll is 1d6:

advantage for a skilled operator (if you do not have skills in your game a relevant PC class will also do)
disadvantage for an unskilled operator
disadvantage for not being accustomed to this machine
disadvantage for using wrong supplies, like metal ore in a wine-brewer. If successful the result might be useless (rusty water), or surprising (IRN-BRU).

The BREAKDOWN roll is 1d6:

advantage for using wrong supplies.
advantage if the machine was not set up.
disadvantage for a skilled operator

After rolling, check all the following conditions:

If the OPERATOR roll is better than the BREAKDOWN roll, the machine works fine and does what it should.
if the OPERATOR roll is worse than or equal to BRREAKDOWN, the machine makes/does something bad, wrong, or bad and wrong.
if the BREAKDOWN roll equals HEALTH, nothing is wrong, but wear and tear reduces HEALTH by 1.
If the BREAKDOWN roll is over HEALTH, roll 1d8 on the CATASTROPHE table.

In case of Catastrophe roll 1d8

The machine EXPLODES. 3d6 damage to everything in the blast radius. The blast radius is 10 feet or twice the size of the machine, whatever is bigger (e.g. a 20' wide machine will shrapnel with a radius of 40'). If present, a demon-core will breach.
The power supply breaks down catastrophically and must be rebuilt. Lose 1d3 Health. Demon-core breach: 4-in-6.
The energy supply thrashes and deals 2d6 damage to 1d6 people nearby, save for half. Lose 1 Health. Demon-core breach: 1-in-6
The machine falls apart some. Lose 1d3 Health.
The usual health and safety accident: a person nearby at random is hurt, 1d8 damage. Loud cackles and cheering from the demon-core.
The machine does or produces something, something somewhat ok but overall very wrong. Decrease Health by 1.
The machine groans horribly from structural stress for 1d6 rounds, then roll again.
Nothing? Seemingly nothing? in 1d6 rounds roll again with advantage.
There may be a weird flash, or eerie clang, or a strange smell, but nothing bad happens.

In case the machine is not powered by a demon-core, ignore the demon-core section.

In case of demon-core breach, the demon core containment fails. The spirit is released with a magic explosion dealing 1 damage per HP of the contained spirit to everyone within 30 feet, save for half. There are ways to open safely a demon-core, but this ain't it.

A List of 1d12 Machines

a star-concentrator for sideral siderurgy. A forge strapped to the end of a telescope on an equatorial mount, tracking a specific star all night to better focus its energy on the metal.
poisonous frog squeezer/breeding-pools, supplying antidote juice.
a 30 feet tall balsa-wood mecha roly-poly, really fast when rolling.
a pharmaceutical omnireactor: makes potions supplied with water, herbs, and alcohol
a car. You might think this having a car would be boring, but I'm willing to bet that your players feel differently.
self-catapulting glider
electrocuting-net automatic fishing/fryer machine
a power condensing empowering pyramid, focusing energy from all its sides on a single point (useful for enchanting or empowering items)
An essential spirit distillery. It splits the content of its pot in separates essences and stores them in jars.
Dinosaur Kerogenator/Distiller. Slightly a misnomer, it converts organic matter in flaming oil (not only dinosaurs).
The Iron Replicator. A self-propelled digger/smelter/forge with the size and mood of a grumpy cow. If fed combustible it will dig and smelt more iron to make more Iron Replicators. To prevent it from dangerous runoffs it has behavioural directives stopping it from feeding autonomously and scavenging iron. In case of Catastrophe the created Replicator will not have those directives.
The Patented Holy-Auto-Card-Maker. A small letterpress/papermill/hemp harvester/graveyard device. You must supply the corpse or ashes of a saint and some hemp seeds, and a whole lot of cranking.