Overview
STEM is a steampunk tabletop RPG set in Acriedal, a world shaped by human and gnome arrivals, steam power, airships, trains, electricity, old wars, and the dangerous rediscovery of Domus.
The current alpha is a work in progress. The goal is fast table play, clear character identity, practical crafting, and adventure hooks that can grow from small jobs into expeditions across the New Lands.
Lore
Thousands of years ago, humans and gnomes arrived in Acriedal. Some people welcomed them, while others feared the madness they were fleeing and answered with steel. Wars followed before a fragile peace formed.
During those wars, humans and gnomes shared steam machines, airships, railways, and electricity. Great steam-powered cities rose, first under human control, then with gnomes, dwarves, and other peoples joining the new industrial order.
Sarah Lightstar, an apprentice historian, found an ancient journal in the Imperial Library. It told of the journey from the lost land of Domus. Her work inspired champions to retrace that route, turning Lightstar into a bustling city for adventurers, relic hunters, engineers, and troublemakers.
Core Rules
Most risky actions use one quick check:
2d6 + Stat Modifier + Skill Rank vs Target NumberTargets
6 is easy, 8 is standard, 10 is hard, 12 is extreme. The Game Master can adjust by 1 or 2 for cover, tools, pressure, damage, or clever preparation.
Skills
Skills run from -1 to +3. A rank of -1 means no real training, +0 is basic familiarity, +1 is competent, +2 is professional, and +3 is expert.
Effect
When the exact degree matters, subtract the target from the final result. Higher effect can mean faster repairs, cleaner crafting, stronger social leverage, or extra combat impact.
Combat
Combat can use initiative or a looser scene flow. Attacks are checks against a target, with cover increasing the target and armour reducing incoming damage through Soak.
Characters
Characters use four core stats: Strength, Agility, Education, and Charisma. Generate each score with 3d6, keep the best two dice, then convert the result into a modifier: 2-5 is -1, 6-8 is +0, 9-11 is +1, and 12 is +2.
- Choose a race, such as human, elf, dwarf, or gnome.
- Choose a background, career, and fixation.
- Pick skills from the general list and from those choices.
- Start with 500 Steam Credits for equipment.
- Calculate Health from Strength plus Agility scores.
Talia "Scrapshot" Vorn
Street Rat Hunter, Survivalist. Strong Education and Strength, with a curved bow, short sword, and padded armour.
Kael "Whisper" Mercurian
Street Rat Explorer, Alchemy Enthusiast. Balanced stats, with an alchemist kit and rifle.
Juno "Ironfist" Vespera
Tinker Martial Artist, Steam Pioneer. Agile and tough, with a curved sword and tinker kit for Mechanoid work.
Valen "Silverfox" Draekhart
Charmer Hunter, Strategic Genius. High Charisma and Agility, with a shortbow and padded armour.
Equipment and Crafting
Equipment matters as much as character numbers. Weapons provide damage, armour provides Soak and Durability, ammunition can improve attacks, and tools unlock engineering, alchemy, gadgeteering, and repairs.
Crafting uses the same 2d6 engine. The Game Master sets a target based on complexity, then materials, workshop access, and skill ranks decide whether the item is flawed, standard, or excellent.
Vehicles are part of the long-term dream: airships, steam trams, trains, hand gliders, hired crews, and eventually custom vehicles or even walking city scale play.
Threats
Mad Ones
People warped by red dust, marked by bright red eyes, pack violence, and leaders carrying strange gems. Starter stat: attack +1, damage 1, life 8, soak 0.
Mechanoids
Steam machines built for work and later war. Many now act on broken survival instincts. Starter stat: attack +3, damage 3, life 10, soak 4.
Sabar Tiger
Huge colour-shifting predators that stalk forested regions in pairs. Starter stat: claw +2 damage 2, bite +3 damage 4, life 12, soak 5.
Faction Agents
Agents of houses, cities, and rival powers who want the Lightstar family weakened or removed from the New Lands.
Game Master Notes
STEM has no heavy level structure yet, so early balance should start small. Use a few Mad Ones, small Mechanoids, or one clear environmental problem before scaling into larger expeditions.
Good STEM encounters ask players to combine people, machines, terrain, and resources: repair the gate, negotiate with a farmer, salvage cogwork parts, keep a train moving, or decide whether a malfunctioning machine is enemy, tool, or clue.
Starter Adventure: Steam Gate Tavern
The party begins outside the Steam Gate Tavern as Lightstar wakes. The city gate grinds open, steam vents hiss, and workers from the farmlands pour into the streets.
On the tavern notice board, a nearby farm asks for unaffiliated adventurers. Old steam-powered plowing machines have gone rogue and taken over the fields. The group must reach the farm, enter the small moat-and-bailey settlement, speak with the master farmer, destroy or disable the Mechanoids, and return with parts as proof.
The reward is Steam Credits, salvage, and the first hint that old machines across the New Lands may be waking up for reasons nobody in Lightstar fully understands.