Dark Earth Magic System

I haven’t posted in a while, but here’s my plan for Dark Earth‘s play-testable magic system.  For now it uses the spell list from d20 (converted using the rules below), but is also dependent on the Toughness save mechanic (as in Mutants & Masterminds) that I’ve imported into DE.

Right now, characters have the option of increasing their Magery value by +1 per level by taking a “Magic Use” focus, forsaking a “Fighting” or “Expertise” focus for that level.


A character has a number of spell points equal to their Magery value.

Spells are cast by expending these spell points.

Each spell has a level, from 1-5, indicating its power relative to other spells.

The spell levels also determine the cost, in spell points, of casting a spell:

1 1
2 3
3 5
4 7
5 9

Spell points regenerate at a rate of 1 per hour (1 per 6 turns).

Spells must be learned before they can be cast.

To learn a spell, a magic-user must study the spell for a number of hours equal to its level.

Once learned, a spell may be cast any number of times, granted enough available spell points.

When converting a spell from the d20 system, the following rules apply:

  1. Saves are made using the corresponding Dark Earth ability as the save bonus (Fort = Endurance, Ref = Dexterity, Will = Perception)
  1. Save DCs for DE spells are equal to 15 + the caster’s Intelligence + the spell level.
  1. Damage is converted by finding the maximum spell damage, halving it (round down), and subtracting 1.

Example: a single magic missile does 1d4+1 damage in the d20 system. Its maximum damage is 5. Half of this is 2.5, rounded down to 2. Subtracting 1 gives a final damage bonus of +1.


A spell may be cast when insufficient spell points are available, including spells of higher level than would otherwise be possible.

Doing so requires the magic-user to save against non-lethal damage equal to the number of spell points by which the cost of the spell exceeds the caster’s available spell points.

Any result other than “unscathed” on this Toughness save causes the spell to fail.

Negative spell points can be accrued in this manner, taking extra time to regenerate, as well as adding to the non-lethal damage of future deficit casting.


A magic-user begins play knowing a number of spells equal to half her Intelligence value.

These spells may be of 1st or 2nd level.


Our campaign sandbox.

To me, the essence of RPG world-building is the map, and I’ve come to like the 6-mile hex map (for ease of navigation).  A map allows players to get their bearings, imagine their surroundings, and know quite precisely where their characters are.  It gives them an idea of the economy of the game world, and when playing ACKS, it also lets them know just where the “borderlands” and “wilderness” are relative to their party and their starting city.  It also provides me with a peg-board for inserting pre-generated modules.  Consider the following maps:

Map #1: The Kingdom of Ervala

This is the regional map for the campaign, in 24-mile hexes.  On the city side of the red line is civilization, with the hexes against the red line being the borderlands.  Outside the red line are wilderness hexes.  These three hex types are important in ACKS for determining various things regarding land-holdings and strongholds.  At 17.35 you can see a unique icon: this is where I’ve placed the Temple of Elemental Evil in my campaign.  19.34 could easily be The Keep on the Borderlands, and Into the Unknown could be anywhere at all, really.

Map 2: The Radfell/Anda Region

And here’s a zoomed-in version of the above map, in 6-mile hexes, focusing on the area around Radfell (a Class III Market), and my slightly-modified Temple of Elemental Evil.  I’ve changed the religious nature of the temple to be in line with my campaign pantheon, but it’s otherwise right out of the box.

So there are greater and lesser sandboxes here.  The smaller, more detailed one, has the Temple in it, which should keep a party of level 1-2 characters occupied for many levels more.  If they should desire to branch out or go to the big city, or even buy a ship, the region is there for them to do so.  Idrana on the first map is a Class I market, and should have anything they might want to purchase.

Nothing prevents them from trying out the Temple, deciding it’s too tough, and seeking gentler pastures.  I’ve included a mine outside of Grunfelt that might be beset by bandits or goblins (or PCs), and if they so desired they could go deal with that for some extra gold.  I have made at least one competing group of NPC dungeon-delvers to shake things up for them if they get slow, but otherwise it’s just … a world.  They can do what they want in it, and I add detail and polish as I have time.

Parthia: The Kingdom of Night

Banner of Parthia

Parthia is a kingdom ruled by a vampiric aristocracy, established following a coup by a particularly composed and long-sighted clan of vampires.  They infiltrated the aristocracies of Eastern Varelia unknown centuries ago, and eventually gathered enough influence and prestige to wage open war against the Emperor, establishing the independence of their realms 200 years ago.  Their armies were smaller, as few would serve them, but they themselves struck in the night at the Imperial chain of command, sending their enemies into disarray and forcing a peace that secured their independence.  Following their success, all domains in Eastern Varelia were turned over to vampiric rule, with the mortal aristocracy sent into exile in the west.

The Parthian clans do not behave like other vampires, and never have.  The others are driven mad by their hunger for blood, but the Parthians have ever retained their senses and judgment.  They were quite deliberate in their plot for control, desiring to move away from the vampiric equivalent of the hunter-gatherer lifestyle and towards a more pastoral arrangement.  They consider their mortal subjects their herd, and they are the shepherds.  The beating heart of this arrangement is the blood tax extracted from the residents of all Parthian domains.  In the interest of keeping the public peace, children and the elderly are exempt from the blood tax, and it is a testament to the cunning of the Parthian rulers that this has always been so.  The only others exempt from this tax are those that serve in the armies, so that they may be at their full strength.

The Parthian vampire lords are interested in maintaining this arrangment for a very, very long time, and so conventional taxes are significantly lower than in other domains.  As long as the blood keeps flowing, they are quite generous to their herd, and naturally fiercely protective of it.  Monstrous incursions and threats from bandits are dealt with in the dark of night, efficiently and with incredible brutality.  The mortal Parthian Guard (the standing army of Parthia) is tasked with keeping bloodshed among the populace to a minimum, for obvious reasons.  These elements combine to make the status quo under vampiric rule quite tolerable (if not always pleasant, on account of the mandatory ritual bloodletting).  It must be so, because the Parthians are branded with a tattoo in their youth, and denied the freedom to emigrate.  All ships flying the Parthian flag are crewed only by the Guard and the vampires.  Few other mortals ever receive permission to leave, and those almost always on state business, attending a vampire lord.  Slavery as such is forbidden by law in Parthia, and those who pay their taxes (both gold and blood) and stay inside the borders are seldom meddled with by agents of the state.

The Parthian Kingdom is not expansionist (at least, not on any human timescale), but maintains the Parthian Guard to see to its security in the daylight hours.  Guards who perform their duties well and demonstrate great loyalty are sometimes chosen to join the ranks of the vampires, as a demonstration of upward mobility in Parthian society.  This “tenure” is never mandatory, but allows Parthia to field an elite guard of vampiric fighters to serve as the vanguard of its nocturnal attacks.  This elite guard, in turn, is sometimes granted land to watch over in return for faithful service.

Otherwise, land changes hands in Parthia far less frequently than in other kingdoms, on account of an aristocratic attrition rate of around zero.  In the rare event that a vampiric domain-holder should be destroyed, it is customary that they have personally declared a successor already in the event of an unfortunate staking.  The king of Parthia is the original leader of the Parthian clan, indeterminably old, and has reigned since the coup he lead himself.  His council, likewise, has been with him since the beginning.  Parthia, as such, is a deeply traditional and fairly fatalistic society.  A mortal Parthian might aspire to wealth or home ownership, but land and titles are reserved for the immortal undead.  The Guard is not only a difficult but a dangerous place to distinguish oneself, and most Parthians are resigned to their lot as artisans and farmers who never travel far from home.  If a visitor asks them how they find life under these circumstances, they typically smile and wryly praise the low taxes.

Other nations find the Parthian arrangement unsettling, but the vampires’ dealings with other rulers have been mild and fair since their revolution, which has kept the peace so far.  Varelia still bears a grudge about its lost territory, and has an extensive network of safe-houses for Parthian refugees (and a good number of dedicated vampire hunters to deal with any attempts to take them back across the border).  The secret plans of Parthia’s rulers are the subject of much speculation, but their agenda unfolds under cover of night, too gradually to attract much notice.

Few mortals will live to see what the future holds for Parthia, but even now that future is being plotted in its windowless keeps, by those who live forever in the darkness.

Governance: showing how a nation is different.

It should be apparent by now that I am a big Paradox Interactive fan, and the idea of combining my grand strategy and RPG interests is pretty exciting to me.

So here are my ideas for applying a version of the “government slider” system from Europa Universalis III to RPG world-building.

The idea of the government slider in EU3 is that you have a set of opposed axes, such as “Land vs Naval”, and that moving in one direction along this axis gives you certain bonuses and penalties unique to that particular axis.  I don’t know exactly how I would implement such bonuses and penalties in ACKS, but I think these axes can still be used as a kind of quick “stat-block” to model the government of a nation or domain.

So when you are designing a kingdom, you can answer the following questions.

1. Centralization vs Decentralization

How much power is shared by the ruler with the vassals?

2. Aristocracy vs Plutocracy

What percentage of total wealth lies in the hands of the land-holding aristocracy?  How wealthy is the urban nouveau riche of traders and moneylenders?

3. Serfdom vs Free Subjects

Is slavery allowed?  Are non-slaves free to travel and work as they wish?

4. Narrow-Minded vs Innovative

Are the rulers (and public) traditionalists, comfortable with their way of life? Or are they desiring to strike out in a new direction (politically, religiously, or otherwise)?

5. Mercantilism vs Free Trade

Aside from taxation, how much does the aristocracy interfere with the economy?  Is their interference protectionist, dirigiste, monopoly-crushing, or what?

6. Offensive vs Defensive

Consider the total amount of money spent on military engineering and equipment.  What percentage of that goes to castles, fortifications, and other defensive works?  What percentage of that goes to siege engines and outfitting the army with quality equipment?

7. Naval vs Land

Of total military expenditure, how much is spent on the navy versus the army?  Of total available manpower, how much is allocated to the navy versus the army?

8. Quality vs Quantity

How selective is the military when it comes to deciding who can serve?  Is there a large army from a universal draft (of poorly paid conscripts), or a small and elite standing army of (well-paid) crack troops?

Political variety under feudalism.

Most popular fantasy RPGs tend to gloss over the mechanical details of things like succession law, but world-builders and DMs have a number of interesting options when designing a feudal (or quasi-feudal) society.  Taking my inspiration from Paradox Interactive’s excellent Crusader Kings series, I’ve thought of some options for making your in-game monarchies more interesting and meaningfully different from each other.

A. Decide how gender affects succession 

1. Patrilineal – only males may succeed the ruler

2. Matrilineal – only females may succeed the ruler

3. Sex-Biased – both sexes may succeed, but only if there are no eligible members of the preferred sex

3. Equal – both genders may succeed equally

B. Decide how relatedness is determined

What defines the dynasty (the royal family)?  Are the children of both sexes considered dynasty members, or only those of one gender?  This is important for determining dynasty membership of children born from dynasty intermarriages.  If the child inherits membership from both parents, then they could inherit claims from both dynasties, while if they do not, claims to the other dynasty’s holdings would be considered illegitimate.

C. Determine the order of succession

There are a lot of options here (see wikipedia), but here are some possibilities:

1. Primogeniture – the eldest child of the ruler succeeds following the ruler’s death

2. Rota – the eldest sibling of the ruler succeeds

3. Seniority – the eldest dynasty member succeeds

4. Gavelkind – domain is divided equally among the ruler’s children

5. Elective – the ruler’s highest-ranking vassals select the next ruler

In my game world, the northerly kingdom of Ervala has a patrilineal primogeniture law, rooted in the traditions of their ancient clans, while the militaristic kingdom of Idalos follows a patrilineal elective law, having arisen from an alliance of smaller kingdoms (who selected a leader for their armies, now their elective king) centuries ago.  The Empire of Varelia also follows a patrilineal elective law, but it is not the highest-ranking vassals that choose the ruler, but all of the titled land-holders in the entire domain.  Although all titled nobility are eligible, in practice only the most prominent and powerful aristocrats are named Emperor, as the lesser land-holders wish to rely on them for support and protection.  Although succession is elective at the highest level, lesser Varelian domains predominantly follow the gavelkind law, making Varelia a patchwork domain of many smaller, warring states.

D. Choose a royal council

Running a kingdom is hard work, and Game of Thrones fans will know well that sometimes you can’t trust the one in charge to actually … be in charge.

In a game system like ACKS, where your character can end up in charge of a domain, who says that your henchmen have to actually be your land-holding vassals?  Why couldn’t your personal henchmen include, say, a trusted and charismatic chancellor who can keep your vassals in line for you while you go adventuring?

With that in mind, here’s some jobs you might outsource to (or augment with) a ruling council, taken right from the Crusader Kings.

1. Chancellor

The Chancellor is the ruler’s right-hand man/woman, with all the political know-how and charisma that the ruler didn’t develop while, say, dungeon-delving or carousing with the other aristocrats.

2. Marshal

The Marshal cares for and commands the domain’s armies.

3. Steward

The Steward deals with all the economic, taxation, and accounting business of the domain.

4. Spymaster

The Spymaster defends against assassinations, plots and carries out assassinations, and gathers information on enemies foreign and domestic.

5. High Priest

The High Priest ministers to the spiritual concerns of the ruling dynasty, as well as ministering to the populace, while acting as liaison between the ruler and the rest of the spiritual world.

E. Determine the domain’s relationship to religion

If there is a High Priest, that probably means a de facto domain religion, and in ACKS, the possibility of church domains within the ruler’s domain.  Do the church-held domains pay taxes?  Do they pay them to the domain ruler, or to a central church authority (or local patriarch)?

Follow steps A-E and you’ll have the seeds of abundant political intrigue, and a pleasantly differentiated landscape of monarchies and empires.

Next up: governance, or how to summarize rulership styles.

Laws of Pretend Inheritance

One of the coolest things about the Pendragon RPG is the emphasis on generational play, spanning more than one lifetime.  This epic scale is something I also really love about Paradox Interactive’s Crusader Kings series.

So while I was out hiking the other day, I thought up a quick and fun way to start a dynasty for your RPG.  This would work particularly well with ACKS domain rules (and an aristocrat class!), and reminds me of the Punnett Square, which I was thinking of.

You’ll need two genetically compatible parents, and one d4 (or in this case, a d20).

For each of the child’s attributes, roll your d20.

On a 1-5, the child receives the mother’s attribute value.

On a 6-10, the child receives the father’s attribute value.

On an 11-15, the child receives the average of the parents values.

On a 16-20, the child receives a randomly determined value, as in character creation.

I haven’t done the math, but at first glance it seems this method would produce royal families whose average attributes were noticeably skewed towards those of their progenitors.

The interplay between status and Charisma value would be interesting to model here, because assuming that both status (wealth) and Charisma contribute to attractiveness and genetic fitness, then those without wealth but with high Charisma would be more likely than those with low Charisma to breed with the wealthy, and so forth.

You could add social status to Charisma to get a new value (Aristo-fitness?), and when world-building, have the mates of a given aristocratic NPC have this same value.

A less charismatic mate would then be of higher status, indicating perhaps an “arranged” marriage of political convenience, while a more charismatic mate could be of lower status, having charmed their way up the ladder a bit.

Depending on the relative values of “Charisma” versus “Social Status”, this could also reliably model an aristocratic taboo against marrying too far beneath your rank, as even the most charming peasant couldn’t expect to marry an Emperor or Empress.

The Dark Earth System

Hi everybody,

This is my world-building and RPG blog, but also a launchpad of sorts for my nascent game system (and accompanying setting), Dark Earth.

I am a younger gamer, in my 20s, and I got my start with RPGs with a strange mix of systems, including Palladium’s Robotech, the Alternity system, and D&D 3rd edition.

I have played a number of systems in addition to those, and comparative game design has become a kind of hobby of mine.  A while back I discovered ACKS, and through it the whole “Old School Renaissance”, which hearkens back to a time that I wasn’t actually around for.  In short, I was deeply impressed.

Looking into the OSR through the lens of ACKS gave me insight into the lasting appeal of D&D.  There are some elements to this kind of gaming that I particularly appreciate:

  1. The emphasis on a kind of existential “thrownness” and fairness-through-randomness. (epitomized by rolling 3d6 down the line for attributes)
  2. Simplicity in design, user-friendliness. (quick character creation = replaceable characters!)
  3. Baked-in risky rewards/motivators (gold = XP, monsters love gold)
  4. A sense of autonomous behavior of the world itself, allowing sandbox play and enabling a DM to better avoid railroading.

When designing my own game system, I wanted to include and emphasize these elements, while incorporating design elements from other games that I also really like.

Dark Earth is thus a “Franken-system” of various game content, and exists primarily to streamline the implementation of various changes to the basic d20 system.

It uses six familiar attributes (Strength, Dexterity, Endurance, Intelligence, Perception, Charisma). These are rated on a scale of 1-10, with 5 being the human average.  Their full value is used for various skill rolls (d20 + DEX to Sneak, d20+INT to Pick Locks, etc), and half of their value is used for various derived attributes (Melee & ranged attack bonuses, Toughness, etc)

There are no skills.  Any humanoid character can do anything a humanoid character can reasonably do, and their basic proficiency at these things is shown by their six abilities.  Importantly, some characters are significantly better than others at certain things, by means of Specialties and Proficiencies (see below).  There are no classes.  At least, not exactly.  (Existence precedes essence: you are a human magic-user, not a mage)  Dark Earth does use levels, because even “level-less” systems are point-based progression at the bottom, and +1 is simpler than +5-6.

There are no hit points, because I prefer a system of abstraction for injuries with higher informational content.  The current version of DE uses basically the same damage/toughness system as Mutants & Masterminds 2nd edition.  Weapons have a fixed damage, and this determines a Toughness save DC.  Your margin of failure determines the actual results of the hit, from a mere bruise to d20’s familiar “dying” condition.

There are hit locations! This might turn out to be too clunky after play-testing, but as it stands, injuries have a location/type.  There are bleeding wounds, and also wounds that negatively effect each of the six attributes.  Characters can make “called shots”, adding a layer of tactical depth.

Like skills, everyone has access to combat tricks.  Wanna try to trip someone?  Go ahead.  Wanna wind up your attack for extra damage, at the cost of telegraphing it, as with d20’s Power Attack feat?  Just tell the DM before you roll.

Besides their attributes, characters are primarily differentiated by “specialties.”  As it stands, a holy trinity of them: Fighting, Magic Use, and Expertise.  You pick one of these each level, arguably making this a “modular class system”.  Proficiencies further differentiate characters. These function roughly as in ACKS, but they are all available to any character, and can be chosen on every odd level.

Dark Earth is, and should remain, a simple game: a 1st level character needs to roll their attributes, choose a specialty, and choose a proficiency.  Like M&M 2nd, all rolls use a single d20.  So far, all relevant character information can fit on a single sheet of paper (I am doing my best to keep it that way).

It is intended as an engine for perpetually gritty, low-magic campaigns.  Simplicity serves the dual purpose of enhancing accessibility and easing the transition to a new character, as mortality should remain high by default.

Monsters in Dark Earth function more like their horror-film counterparts than their D&D equivalents.  Goblins are terrifying abhuman man-eaters, Ogres are wrathful, hulking murderers of literally skull-crushing strength, and Dragons work as one would “realistically” expect a giant, flying, armored, fire-breathing lizard to work.

The only problem with just running away from them is that they’re always standing between you and something you want.

The only problem with staying to fight is how attached you are to those nice stats you rolled.

More to come soon, including game mechanics.