Plebeian Preview: Magic

28 Sep, 2026

Something must be in the air, because it seems like everybody is blogging about magic. I read Nael's post about magic and thought I might have something of interest to share.

I'm working on a game right now called Plebeian which is designed to support funnel adventures as well as traditional, four-to-a-party dungeon fun. It has no ability scores and no classes, and uses kind of a spin on Mythic Bastionland's combat rules. Each PC has a set of dice they can roll each round: the more dice, the more things they can do; the higher the number rolled, the quicker they can do them. When a PC levels up, they can increase the number of their dice, the size of their dice, or other stuff like learning a spell or increasing the number of Hits they can take.

Below, I'm going to share some snippets from my rules document draft along with a smidge of commentary on how I hope things will work in play:

Magic

Every spell has a Cost, which is the number of Action Dice required to cast it. These can be spread out over multiple rounds, but must be consecutive: if the casting of a spell is interrupted, all progress is lost and the caster must start over. Given time (about 10 minutes), a mage can "take 1," gaining only 1 Toll per 1 Cost of the spell.

When a spell is cast, the sum of the results on the Action Dice used to cast it is added to the spellcaster’s Toll. Every 5 Toll, something unpleasant happens to the caster, though the spell is still cast.

All Toll is removed after a week resting in a safe place. Mages can extend a spell’s duration indefinitely by keeping the Toll they accumulated casting it.

I personally dislike it when games make arbitrary rules constraining your choices, like "Wizards can't wear armor." Instead, I like to create systems where that behavior is incentivized without being categorically prohibited. As you'll see later, spells can have quite powerful effects, but casting in combat carries a substantial risk to the mage and their allies. The amount of Toll inflicted on a mage is directly proportional to how quickly the spell is cast, so a mage may choose to roll lower-size dice than they're entitled to to minimize magical backlash, but this also leaves them open to getting interrupted or targeted by enemies. On the other hand, a martial character may dip into magic so they can still get utility out of low rolls.

Complications

Roll 1d6. When a complication refers to [Toll], it means your total accumulated Toll when you roll that complication.

(1) Feysickness: Metal burns you for the next [Toll] hours. If wearing armor, it will burn you for 1 Hit before you can get it off.

(2) Fatigue: Your Action Dice become d4s for [Toll] hours.

(3) Backlash: Your spell creates an explosion of magical mischief. Treat as a single attack of [Toll]d4 against you and those nearby.

(4) Silence: You may not speak (i.e. cast spells) for [Toll] hours.

(5) Sacrifice: You must provide a treasure sacrifice of 100 x [Toll] coin or blood sacrifice of 1 Hit x [Toll] to your patron or god by the next full moon (in d30-1 days, if uncertain).

(6) Calling: A rival mage sends an invisible stalker ([Toll] Hits) after you. It reaches you in d30-1 days.

This is a very simple list of nasty side effects, but I quite like it. As you'll see, spells can be quite powerful, but Feysickness and Backlash can straight-up kill a weak character, meaning that very strong magical effects are last resorts for low-level characters. Fatigue and Silence are complementary: Fatigue basically limits a mage to casting spells, while Silence prohibits spellcasting. While either is annoying on their own, both in combination neutralizes a character, meaning you don't want to stack Toll effects. Sacrifice and Calling are a bit odd, but I kind of like that they give a sort of quest to the character and tell you something about the implied setting.

Sample Spell

TRAMARA’S TRANSPLENDENT TRANSFORMATION

1 Cost: Change an individual’s characteristics within the normal range of its species (i.e. hair/eye color, sex characteristics)

2 Cost: Change an individual’s characteristics beyond the normal range of its species (i.e. exceptional height, number of digits/limbs)

3 Cost: Give an individual characteristics of a different species (i.e. gills to breathe underwater, fangs/claws)

4 Cost: Completely transform an individual physically, keeping their mental attributes the same. If slain, they revert to their original form.

5 Cost: Transform an individual physically and mentally. If slain, they revert to their original form.

Mages can only learn about 1 spell per level, so each spell should be quite versatile. I like the way Whitehack does things, but I wanted to have a non-exhaustive list of example effects so that players and GMs had some idea what their powers could do. As you can see, this spell is quite powerful: at low to mid costs, it has obvious utility value for any number of puzzles or social situations. At its maximum power, the spell could be used to turn an ally into a powerful monster or an enemy into a harmless pest. But (ideally) the rules for Cost and Toll incentivize creative thinking and problem-solving while limiting very powerful effects to one-off situations or emergencies.

Magic Subsystems

These are less defined ideas, but the mechanics for magic suggest rules for scrolls, arcane foci (like staves and wands), and familiars. Here are some passages concerning those:

Scrolls

Scrolls can be used to cast spells a mage has not yet mastered.¹ Anyone who knows any spell can cast from scrolls. A scroll has a set Cost (i.e. 2 Cost, "Change an individual’s characteristics beyond the normal range of its species [i.e. exceptional height, number of digits/limbs]") and tolerance for Toll (i.e. 5 Toll).

A mage casting from a scroll uses their Action Dice as normal to cast the spell, but may choose whether to take on the Toll themselves or imbue the scroll. A scroll is destroyed when it reaches its tolerance; if there is any excess, the spell fails. A scroll’s Toll is permanent, but so are the effects that Toll was incurred to cast.

Arcane Foci

An arcane focus is a powerful magical artifact facilitating the use of specific magic. The type of focus determines how it facilitates this:

Wand: Adds more dice (more dice and smaller size = better wand): Wand of Fireballs: +2d4 to casting fire spells

Staff: Can “store” Toll on a mage’s behalf up to a certain maximum and regularly clear it (higher maximum and quicker regeneration = better staff): Serpent Staff: Store up to 5 Toll casting serpent spells, clears 1 Toll at each moonrise

Orb: Reduces Toll to a certain minimum (higher amount reduced and lower minimum = better orb, can be extremely powerful): Ponderous Orb: Reduce the Toll from scrying spells by 1 (minimum 0)

Familiars

Familiars are a kind of minor magical patron, magical creatures which sometimes take the form of beasts and offer arcane knowledge in exchange for favors. A mage can only have one familiar at a time. That familiar permits them to cast a spell as if they had mastered it through leveling up, but the familiar requires some kind of regular payment or services.

Imp: Knows Marniel’s Marvelous Malady, wants children’s tears (1 crying child/week)

Raven: Knows Corcoran’s Complex Comprehension, wants scrolls (1/week) or unique tome (1/month)

Symbiont: Knows Tramara’s Transplendent Transformation, wants flesh (1 Hit’s worth/day)

Footnotes

#osr #wip