Lex Arcana Review

Happy New Year! I’m here today with something that I’ve been chipping away at for the whole holiday season, which means it’s pretty long. Normally I’d split this sort of thing into a few different posts but I’m so into this game that I just want to start the year off with a massive post!

Lex Arcana is a game of fighting supernatural threats as an elite soldier of the Roman Empire. That right there was enough to hook me but it’s also beautifully designed and has 25 years of history as an Italian RPG produced by Quality Games. Let me talk (at length) about why I think this game is awesome but I also want to say that if you like Roman games generally be sure to read the Encyclopaedia section. It might be the tastiest cherry on top of a game that I read all last year.

The Setting

The world of Lex Arcana is an alternate history of the Roman Empire set in 476 CE with a few changes. Rather than being at the end of its existence in the fifth century, Rome has kept its territories stable for about 300 years after Hadrian’s decision to stabilize the borders (it didn’t work in actual history but in Lex Arcana he succeeded). This means that the Roman Empire is still unified and expansive in Lex Arcana’s version of 476, and also that the Empire has weathered storms well so citizenship is more universal and territories are connected and customs have shifted with new populations. Among other things, this also means that the stronger social position of women in Germanic and Celtic communities has become part of Roman society too.

The other change is that Christianity was not adopted as a Roman religion by any emperors and as such remains on the fringes and generally ignored by the polytheists of traditional Roman culture. I really looked hard for a reason for this and came up empty. This is a shame because it seems lazy next to the enormous detail exhibited by the book in general. It’s also seems to be implying that A) Christianity never would have gone anywhere if it weren’t for a celebrity endorsement by Constantine, and B) Christians were benignly “tolerated” (the book’s words) up until the religion’s adoption by the Roman elite. I don’t want to go off on a tangent here but both of those things are wildly wrong to a degree that actually makes me mad. It’s a good thing the rest of this game is really compelling…

Image © Quality Games

Player Characters

Let’s start with who PCs are in this game and what they do. Your character is going to be part of the Cohors Auxiliaria Arcana, the Auxiliary Cohort of Secrets. Throughout Roman history, according to the game, there have been supernatural threats to the Empire and they were dealt with as needed by legionaries, local militias, or canny commoners. Now, though, the portents turn to a great existential threat that could end the empire and so the emperor announces the Lex Arcana, a new law which tasks his elite Praetorian Guard with stopping all otherworldly threats.

The Cohors is set up with custodes, guardspeople who are recruited for this specialized person. After basic training they are sorted into a specific training program (a tirocinium) at the end of which they are initiated into the cult of a Roman deity to serve the Cohors in a specific way. Fighters are inducted into the cult of Mars, explorers into the cult of Diana, augurs into the cult of Apollo, scholars into the cult of Minerva, and diplomats into the cult of Mercury. The last bit of training that a custos gets is joint training with their contubernium, a group of 3-6 custodes from all different training programs. In other words, an adventuring group.

All of this parallels the character creation process in Lex Arcana. Your character starts off with points in six Virtues which act like attributes in other games: the Virtues of the Body (Coordination and Vigor), the Virtues of the Mind (Authority and Intellect), and the Virtues of the Soul (Reason and Sensibilities). You can determine this randomly or through point buy but it will probably inform which of the Offices of the Cohors your character ends up in. In addition, characters have Peritiae (the Latin word for “practical knowledge”) which also number six: De Bello (fighting knowledge), De Corpore (athletics and stealth), De Magia (magical knowledge), De Natura (wilderness knowledge), De Scientia (scholarly knowledge), and De Societate (social skills). You also have Specialties under each Peritia which represent things you’re particularly good at: you might be decent with De Natura but especially good at hunting, or terrible with all things De Scientia except for your strong grasp of investigation.

Image © Quality Games

Your Peritiae get modified based on your Province and your Virtues get modified based on Age. You get a combat talent from your office (something special that your sort of Custos gets to do) and both hit points and Pietas from your stats. Pietas is a spiritual point pool that you can spend, among other things, to call on the favor of the god of your Office’s cult. There are some complex diagrams and some math involved but it’s fairly straightforward in the end. Character advancement is also pretty cool since you get to point buy how quickly each of your Peritiae increases and also how quickly you gain ranks and your godly connection through your cult. This is a granularity that I didn’t expect to like but I think it’s cool.

Advancing in the Mos Arcanorum (the “Conduct of the Secrets”) gets you farther in the Cohort itself: you get a higher title, resistance bonus (for more staying power), and some benefit options. Benefits make you generally better at your job and you can choose from an increased Virtus score (Peritiae are much easier to increase), getting better equipment, or gaining an assistant or trained animal. If you’d rather (or in addition) you can also advance along the Pax Deorum (the “Peace of the Gods”) which is, simply put, spellcasting. Spells of the Choros Arcana are called indigitamenta (“invocations”) and they involve calling out to one of the gods of the Empire for aid. More on that in a bit…

Image © Quality Games

Mechanics of Play

When you want to do something, you use one of your Virtues or one of your Peritiae to determine the size of the die. If you are trying to figure out whether someone is being truthful then you might roll Sensibility, while trying to figure out the true motivations behind a new law would be De Societate. Sometimes there is real overlap like if you’re talking to a senator who is explaining the reason for the law and you want to know if he’s lying. In that case, I think you just go with the highest one. If you use your practical Peritia knowledge, though, you can apply one of your specialties. The better the score of the attribute, the better the die you roll, and the more likely you are to beat the target difficulty.

However, there’s one aspect that makes this system not just thematic but also really interesting for game design. Your attribute score doesn’t directly translate to a size of die, but rather to a die size. The dice options include all the standards d4 through d20, but also d3 and d5. When you roll, you can roll any die or combination of dice that have a maximum value at least equal to the Virtue or Peritia + Specialty total. So with an 8 in the relevant attribute you can roll a 1d8, 2d4, or even 1d5+1d3. Rolling multiple dice gives you more of a bell curve probability while rolling single dice (or fewer dice) gives you a better chance of getting a high result but also a better chance of a low result.

In addition to this is the “fate roll” which is that dice explode (roll again) when they roll their highest value. So if you had the 1d8 from above and you roll an 8 then you roll again and add to the result. If your second roll is also an 8 then you just keep going. This also works for rolling 8s on 2d4 or 1d5+1d3, though you’re more likely to get a middle result. More dice is a safer roll but fewer dice has the potential for real payoff. So there’s some dice strategy going on since you can decide how much risk you’re taking on your roll and you can also translate that into the narrative: rolling 2d4 might be rushing down the stairs after your quarry while rolling 1d8 is grabbing a rope and leaping off the balcony.

Image © Quality Games

I realize I’m spending a lot of space on just the mechanics of rolling dice and roleplayers are already more than familiar with the process, but the beauty in this elegant system just floors me. Each roll you have a wide, branching tree of decisions and you can Beautiful Mind the whole thing out but each decision is also intuitive and the difference between your best and worst options is usually less than five percentage points. You can always say “I think I’d like to use my Coordination here” and the GM (or “Demiurge”) says “alright, try this.” You can also pick 3d4 instead of 1d12 just because you like fistfuls of dice and it really doesn’t hurt your chances much. I love it.

Indigitamenta (Spells)

Every Custos gets the indigitamentum of their Office (mentioned after Pietas above) but if you get more invested in the mystical side of things you can also gain other indigitamenta. There are many for the official gods of Rome, some of which are other aspects of the Offices’ patron gods: Augurs, for example, automatically get an indigitamentum for Apollo Pheobus (Bright Apollo) to help their De Magia rolls but they (or others) could also learn to call on Apollo Articenens when using a bow and arrows or Apollo Paean for recovering Pietas to cast more spells. There are also the other big gods in the pantheon who don’t have a specific Office under their but have indigitamenta that you can learn through advancement: Hekate, Jupiter, Juno, Neptune, Prosperina, Pluta, Venus, Vesta, and Volcanus.

Any Custos can get any indigitamentum but they each have “privileged Offices” that get a better effect. For instance, calling out to Jupiter the Predator gives your contuberium automatic successes on an ambush. When used by an Explorer specifically, though, that Custos also gets a damage bonus on their first attack. Once you use an indigitamentum (and paid the Pietas cost) you can’t use that particular invocation again until you’ve visited a temple of that god and offered some prayers.

Image © Quality Games

Additionally, there are indigitamenta to the Di Indigetes, the local gods of Rome itself. These are figures that were historically pretty limited to Rome, or at least to Italy, and include gods like the Sabine war goddess Bellona, the two-faced god Janus, and the harvest god Saturn. These indigitamenta have some pretty nice abilities and follow most of the same rules as the invocations of the official pantheon, with two exceptions. First, there are no privileged Offices for the Di Indigetes, they give the same benefit to anyone. They don’t like to be bothered too much, though, so if one Custos invokes their favor and then another in the same group tries they’ll ignore the second plea. These are specialized options. Secondly, you don’t necessarily get the god’s ear when you call on them. Since these are focused, local deities you need to make a Virtus roll to see if they hear you and the Difficulty depends on how far you are from Rome. Failure means that you have to pay extra Pietas equal to how much you failed by and if you can’t afford it then the god just can’t with you right now.

Additionally, there are rituals of divination, a type of magic that is central to the Roman spiritual experience. This is a different definition of “divination” than other roleplaying games and includes both knowledge of the world but also the opinion of the gods. There are six disciplines of the Art of Divination: precognition (knowing the future), clairvoyance (seeing or finding things in the present), retrocognition (seeing the past), interpreting omens in the real world, interpreting dreams while sleeping, and perceiving the favor of the gods (whether something will please or anger the gods). All Custodes learn a basic set of eight rituals covering things like reading the gods’ will in lightning bolts, interpreting birds in flight, reading the gods’ desires in animal entrails, and watching the stars. Custodes can learn other rituals in their career, even ones of foreign gods and forbidden cults. However, if you are caught doing unsanctioned magics then you can be temporarily suspended (for a tolerated cult like Christianity or Egyptian gods) or a exile and death (for a forbidden cult like druidic practices or Egyptian necromancy). Perhaps more seriously, the gods themselves take a dim view of unofficial rituals and might give the Custos a cold shoulder or even turn against them entirely.

Image © Quality Games

As a last bit of magic, the game includes the sortes which are part of a Custos equipment and some of the game materials. Your character might use their sortes to get some knowledge of the future but as a player you’ll be using them to draw and gain a mechanical benefit that you keep secret from the rest of the table. When you want to use your sors, you flip it face up and read it off so that you can suprise the Demiurge (and the rest of the party) with a bonus to a check that was just made or that the Demiurge needs to tell them whether a rumor they just heard it true or not. This seems really awesome and I’m likely to steal it for other games including Invisible Sun.

Adventures and Missions

So what do Custodes do? In short, they investigate any supernatural problems in the Roman Empire and combat any supernatural threats. Sometimes this means confronting cultists of dark forces, sometimes it means fighting monstrosities or demons, and sometimes it means finding supernatural corruption turning Roman citizens into something terrible. In addition to the chapter of NPC and animal stats, players and Demiurges get a short bestiary of such fantastical creatures as Amazons, monstrous animals (like the Nemean Lion or Erymanthian Boar), sacred animals (something more magical than savage like the Cretan Bull), Arachne’s progeny (human-spider shapeshifters), basilisks, Germannic berserkirs, centaurs, chimeras, demons (specifically Azazel, empusai, eurynomes, incubi, succubi, the queen Lamia, the demonic progeny of Lilith, a fallen angel of death called Mashit, and the Assyrian demon Pazuzu), dragons (of Celtic type and ancient Hyperborean dragons), fauns and satyrs, Celtic reapers, giants (Cyclopses, Gegenees, Celtic giants, and Hyperborean giants), Gorgons, griffons, harpies, hydras, leviathans, manticores, minotaurs, nymphs, horned serpents of Cernunnos, sirens, sphinxes, theurgic constructs (automata and living statues), tritons, undead (ghosts and reanimated corpses), Versipelles (werewolves), water horses (from Frozen!), winged horses, and vampires. Whoo!

Image © Quality Games

A typical adventure includes getting an assignment from a superior officer in the Cohors to head out to some small town in the Gallic countryside or Germannic frontier. You get there and things don’t seem quite right and you aren’t sure who to trust, even though you have the power of the imperial seal behind you. Think of this stage as a 5th century version of the X-Files. Eventually the problem becomes clear and the tension heightens. Maybe the threat moves from shadows to open blades and you fight, or maybe the source of mental corruption is revealed and a plan of action is formed. Whatever the outcome players write a debriefing report and get their orders for their next assignment, probably nearby but increasingly spread around the Empire ad they prove themselves.

There’s a really great adventure compendium call Mysteries of the Empire I (and I can’t wait to see what’s in store for the next volume) but in the core rulebook you have two pretty typical adventures: “The Long Winter Nights” which sees the heroes tracking German cultists into the wilderness and “The Mothers of Cenabum” follows the first adventure’s events (though you could skip) with a murder investigation in Gaul. 

The Encyclopaedia

One more part of this game deserves special attention and that’s the background research. This game is a gold mine of setting information for the Roman Empire with thoughtful resources that any Roman campaign could use. There’s a short history of the Republic and Empire (a perfect digest size for lazy players), notes on being a Roman soldier and living in camp, standard military equipment, travel in the Roman world, travel beyond, sending messages, complicated Roman currency, growing up in different stratums of society, Roman food, the gods and religious practices, and a province-by-province look at the late-stage Empire. This is the sort of attention to detail you can also find in Cthulhu Invictus and I mean that as a strong, strong complement.

Image © Quality Games

Then there’s the Encyclopaedia Arcana. This book is similar in scale to the original book (232 pages) but it covers so much. It covers much more about travel and about the infrastructure that Rome built to stitch its empire together. It covers major routes and travel around the individual provinces, caravans through the African and Asiatic deserts, and sights along the way (you can get a sense of this part in a free preview). It has two dense pages on mail within the Roman Empire and ten full pages about sea routes, sailors, and sailing culture in the Roman world. It covers the government of Rome from the top down to municipal leaders including individual civic officials within the systems and the terms to use to speak with them. Do you know what a Comes is or what honorific to use with him? Better brush up before you get yourself in trouble! Similarly, there’s a wonderful discussion of the organization of the legions including all the officer positions, non-commissioned officers, military meals, recruitment, the legionary oath, the four-day training regiment for Roman soldiers, a little bit on how the Cohors Arcana is organized, and fleets and positions in the Roman navy. This is only the first third of the book; there’s more on trade, crops, money, family life, social class, patronage, leisure, city planning, medicine, religion, and a host of other topics.

This is a niche book, to be sure. It’s really just a reference book for the Roman world (purposefully focused on areas besides Rome itself) and not every game of Lex Arcana will make use of it regularly. For those that want to fully immerse themselves in this fascinating setting, though, this book is beautifully written and organized to convey an enormous amount of information in as digestible a format as possible. It’s also mostly focused on showing you what the world is like so you can use this book for any game set in the Roman Empire. Are you running Cthulhu Invictus? Maybe you’re running some vampires through Fall of the Camarilla? Heck, you might even be running Eagle Eyes! Whatever your game, this book is my number one recommendation for a roleplayer’s guide to ancient Rome.


This game has a pretty lofty concept and it does it extremely well. It’s a fantastic delve into the world of the Roman Empire by some game designers that both really know how to design games and who know their source material very well. If any of what I wrote above is appealing to you, I highly recommend you go out and get this book immediately. If you just like Roman games but already have a system you like, then get the Encyclopaedia Arcana to give yourself some awesome setting rules. A great game by a company that clearly loves its work.

6 thoughts on “Lex Arcana Review

  1. “The Cohors is set up with custodes, guardspeople who are recruited for this specialized person. After basic training they are sorted into a specific training program (a tirocinium) at the end of which they are initiated into the cult of a Roman deity to serve the Cohors in a specific way. Fighters are inducted into the cult of Mars, explorers into the cult of Diana, augurs into the cult of Apollo, scholars into the cult of Minerva, and diplomats into the cult of Mercury. ”
    That’s the reason you “looked hard” to…
    It is so obvious that you cannot use the christian religion in a system set in ancient rome and where the intervention of the gods is omnipresent, both as an aid in the actions of the players, as in the magical system.


    1. In think what you’re getting at is that Christian cosmology means the Roman gods don’t exist. There are plenty of other cultures’ gods in the book but I take your point. I’m just saying that the *social movement* of Christianity was talking off in important ways that I haven’t seen addressed in the setting. Maybe it’s in the Encyclopaedia…

      But also Christians were rounded up and killed, they were enslaved, they were brutalized and tortured. I see why the setting wants to just make them a tolerated cult and leave it there but a lot of hugely important late-Empire events would be completely different without pogroms against Christians plus erasing genocide to make a setting more palatable is not the best approach.


      1. Hi Mephit James, I am not the maximum expert on late Roman history or the rise of Christianity, but as an expat living in Italy I have done some reading on the spread of Christianity as well as the Roman persecutions. My understanding is that for the most part Christianity was tolerated as long as it’s adherents weren’t too obvious about their worship and their denying the official Roman gods and the divinity of the Emperors. Furthermore the persecutions tended to target the Church leaders but tended to not go after the followers very much – i.e..the persecutions were by and large neither very thorough nor very ruthless – which is a big reason why they didn’t work in the end. So the postulates of this book are not entirely incorrect.
        However, Christianity grew generation by generation and by Constantine’s time it had reached a level of popularity – especially in the urban areas – that it reached a tipping point that probably also had the effect of encouraging Constantine’s conversion to the up and coming faith. Plus as a monotheistic faith it conveniently fit a One God, One Emperor model which was probably also to Constantine’s liking.
        Admittedly this is a fairly cynical view of Constantine’s conversion, but one that has support from many current historians of that period.


      2. I think that’s probably a good take. Honestly, the more I consider it the more onboard I am with this aspect of things. I do think there’s a feeling of “pagan times were best times and super-metal and could have continued without change if it weren’t for Old Man Jesus.” I don’t think this is that, though, it’s just my grumpy reflex kicking in.


Leave a Reply

Fill in your details below or click an icon to log in:

WordPress.com Logo

You are commenting using your WordPress.com account. Log Out /  Change )

Twitter picture

You are commenting using your Twitter account. Log Out /  Change )

Facebook photo

You are commenting using your Facebook account. Log Out /  Change )

Connecting to %s

This site uses Akismet to reduce spam. Learn how your comment data is processed.