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Author Topic: Lex Arcana II Edition Core Rulebook  (Read 2293 times)


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Lex Arcana II Edition Core Rulebook
« on: August 15, 2021, 11:59:13 AM »
After some 20+ sessions, I'm giving my review of the Lex Arcana 2nd Edition Rulebook.
I'm an old fan of this game since the time of the 1st edition published in Italy in the'90s.

Main theme (Prelude and Chapter 1)
Set in an alternate 476 AD (year of the fall of the Westen Roman Empire in real world), Lex Arcana
 imagines the Roman Empire is unscathed thank to the mastering of magic, in particular divination, that
allowed Rome to avoid the pitfalls that brought its doom in real life.
But in 476 AD the situation looks bad, so the emperor forms a new special unit of the Praetorian Guard,
the Cohors Auxiliaria Arcana (CAA), with the goal of investating and suppressing magical threats to
the Roman Empire.
Obviously, the characters play Custodes, the agents of the Cohors Arcana.

Recruited from different paths of lives and coming from all of the provinces of the empire, the Custodes
are expected to act in very small groups (Contubernium) and with a high degree of autonomy. They also
 benefit from divine help  from Roman gods.

Main Mechanics
All normal D&D dices are used except the d100, d3 and d5 are also used very often.
There actually are five D&D-ish classes  (called cursus - career paths inside the Cohors Auxiliaria Arcana):
 fighter, explorer, diplomat, scholar (doctor/scientist) and augur ("wizard" doing divination/clairvoyance).
 Every class is under the protection of a Patron Roman God, for example Mars for fighters.
 I figured out the classes are cleverly reskinned D&D ones, with the explorer being a ranger/thief type,
 the diplomat taking the role of the bard and the scholar that of the cleric
(as he can heal wounds through medicine/surgery) and, partially, of the thief (as he can detect and remove traps).

The system is almost pure skills and there are little reserved class special power, so for example the fighter
 can try to do divination if the augur is not available. You throw an exploding sum of side dices equal to your skill/attribute
 value against a difficulty set by the master or against a contrasting roll of the monster/NPC (like in combat).
If the PC get the maximum (like 6 on a d6), he reroll and add the result. That's explained in game as the Fate Roll,
 as the PCs, being members of the Cohors Arcana, are assisted by the Roman Gods themselves.
More or less the rules of Savage World, but a lot simpler.

Furthermore, once per adventure, a PC can ask his patron god to help him, this time only in his expertise field
(ie the fighter ask Mars to help him in combat). So the player can reroll the dice and add the result.
If a PC displease the gods, the Fate Rolls disappear and he cannot invoke his patron god.

The rulebook goes in a lenghty description of the character sheet (Chapter 2) and task resolution
 (Chapter 3), before explaining how to actually create Characters. That is somewhat justified because
there are 12 pre-made characters, two for each class. So, one could skip the lenghty chapter 4, read chapter V Combat and
chapter 6 Magic and start playing outright.

There are 6 characteristics, the Virtutes (with D&D equivalents):
- Vigor (StrConstitution)
- Coordinatio (Dexterity)
- Auctoritas (charisma, in the sense of leadership)
- Ingenium (Int)
- Ratio (Wis)
- Sensibilitas (cempathy and also perception of magic/threat).

Theese are seldom used in game, mostly to do checks of raw power (brute force/stamina: vigor; spell resistance :
ratio and so on).
Virtutes are rolled with 2d6, then modified depending of the age of the character (ie older character have more
 Auctoritas and less Vigor)
Then come the six Peritiae, broad skills:
- De Bello (Combat)
- De Natura (Nature)
- De Corpore (Body)
- De Societate (social skill and also politics)
- De Scientia (Science, including tecnology and medicine)
- De Magia (Magic)

Most actions in Lex Arcana involve a Peritia check against a difficulty threshold set by the master.
There are also subskills called specialties, for example Bow, a specialty of De Bello.
Each peritia is generated by sharing the starting values of 2 virtutes. For example, De Bello is made of Vigor
 (that also generate De Corpore)
and Auctoritas ( that also generate De Societate). A province modifier is added to each peritia depending of
the birth province of the character. A character from Rome, has a good modifier in society and science, but poor in
nature, that deal with outdoor activities.

Last stats are Hit Points (Vigor+De Corpore) and Pietas (Ratio+Sensibilitas) that represent the
faith of the character and is used as mana points to fuel spells.

Hit Point determines the maximum encumbrance the character can carry. That it's very important because Custodes
receive equipment (weapons, armor, shields) at no cost, freely given by the empire. But a steep mechanical penalty
force them to drop everything which too heavy for them.

Task Resolution (Chapter 3 & 7)
Most stats (virtutes, peritiae, weapons, armors ecc) are expressed in Dice Points, a value that must equals the
sum of the sides the dices thrown in a check, with a maximum of 3 dices. The result, to succeed, must be over
a target number, called difficulty threshold (DT), set by the master or against the opponent throw (like in combat).

For example, imagine a character trying to follow traces he found in the ground. The master is calling for a DT of 9
and the character has a De Natura (the relevant peritia in this case) of 12. That means that, with a maximum of 3 dices,
the player can choose any die combination that gives 12 as the sum of the sides. So, 1d12, 2d6, d8+d4 and 3d4 are
all legit choices. Then why one should choose 1d12 over 3d4 any day, when the latter would give a better result
 more often? Because if the maximum result is rolled (Fate Roll), the characters gets to add a second round
of throwing. And the probability of doing 12 with a d12 is higher than 3d4.

To qualify the outcome (how much successful), the difference between the roll and the Difficulty Threshold (or the losing
opposing roll) give a degree of success, raging from Marginal (difference 1-3) to Exceptional (7+).

Task resolution in Lex Arcana is very simple...but not easy, because the master must adjudicate
both the difficulty and which peritia is involved. For example, someone wants to swim upriver...De Natura
(knowlegde of rivers), De Corpore (physical training), Coordinatio (dexterity) or Vigor (strength)?
Not quite evident, even if Chapter 7 (the Master) give abundant guidelines and examples.

Combat is a duel between a character against a npc/animal/monster.
There is no initiative, non-engaged characters act first and then, simultaneously the others.
Both opponents rolls their De Bello, the
winner is the attacker and the Degree of Success give a multiplier raging from x1 to x7.
This multiplier is applied to the value of the weapon of the attacker to determine the wounds inflicted.
Let say is x3 and the attacker uses a sword (ensis) that have a value of 3. The attacker will roll not 3,
but 9 sides of dice (a d6+d3 or d5+d4 or 3d3). The defender roll the value of his armor to absorb damage,
taking only the difference.
Missile weapons are similar, but with a set difficulty based on range instead of the opponent's De Bello.

There are rules to cover numerical disparity and combat powers of the various classes and monster, but
everithing is quite smooth and simple, if a bit abstract. It's quite easy to do theater of the mind
and minis is doable but seems too much.

Magic available to custodes is mainly divination, different rituals that allows to
investigate future, past or hidden info about the present. Also, they can allow to
understand the actitudes of the Gods toward them and to interpret omens. Any such
ritual costs Pietas points, that can be recovered after the end of the adventure by  visiting the
temple of the gods.
Another form of magic is Indigitamenta, actual spell that the custodes may learn, that calls
upon the gods to act in their favor. The starting indigitamenta of every character
allows, once per adventure, to ask their patron god to reroll and add in a check of their class
main Peritia (ie a fighter invoking Mars to reroll De Bello during a fight).

Two long chapters gives a bestiary and a description of every province of the empire.
The rulebook includes 2 introductory adventures.

The Core Rulebook is a sturdy hardcover book of 310 pages, looking very robust. Unfortunately, the paper is
a bit too glossy and the art is too bold to me (the iconic explorer wearing a wolf hide) , used to the
 no-nonsense style of 1st edition. Also, the index is a bit too broad in its entries and sometimes the
internal reference, while reliable, is a bit poor. Worst offenders are the rules of poisoning, that forced me
to wade through 3 or 4 references along the whole lenght of the book.
I own the Italian Edition hardcover and the pdf of the English one. The latter seems to me to be
translated well (but, beware!, I'm no native english speaker) and is available through drivethroughrpg.
Not sure if the English edition has ever been printed in book form.

Lex Arcana is a simple game and very easy for the players, but require a strong  adjudicating effort from the master.
The premise is beautiful in my opinion and offer a huge possibility for adventures raging
from every corner of the empire and beyond. Anyway, the fact that you can only be a member
of the Cohors Arcana somewhat limits the choices available to both master and players and could
grow old fast. In my case, after 20+ session, the game still works, but I hope for a future
expansion to widen the scope.
« Last Edit: August 16, 2021, 02:12:05 AM by Murphy78 »


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Re: Lex Arcana II Edition Core Rulebook
« Reply #1 on: August 30, 2021, 06:31:14 AM »
Saw the hard-cover in print at Warp One in Edmonton (AB, Canada), so yes there are print versions in English in game stores. I was curious about it but didn't have much chance to look at it closely (busy running demos).

The idea here of rolling any type of die combination that totals the same number of faces is very intriguing. Certainly plays with the bell curve / probabilities distribution in an interesting way. Thanks for writing the detailed review.


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Re: Lex Arcana II Edition Core Rulebook
« Reply #2 on: September 11, 2022, 04:43:54 AM »
The sword (ensis) has a value of 8, not 3. So you can choose, for damage, to roll 2d4, 1d5+1d3 or a d8.

Sorry, my bad.