Acheronian Edition Rules

Conan RPG Acheronian Edition

This is a set of house rules aimed to repair certain mechanical imbalances in Mongoose Conan d20. High level play (10+) has sorely needed several fixes. The Second Edition of the Mongoose Conan RPG failed to address any of these things. Thus behold this Acheronian aberration that slithers forth to blast your sanity with its unholy rules…. It is based on Conan d20 Atlantean Edition. If not mentioned otherwise, the game still follows those rules.

Attack and Defences

Attack and defence progression has been radically changed. Now it follows 4E/Star Wars Saga guidelines. Every character receives +1 to Attack, Parry, Dodge, Magic Attack, Fort, Ref and Will every even level. (+1 at 2,4,6,8,10 etc) The first character level gives certain basic bonuses. You can only receive a basic bonus once – so multiclassing does not grant basic bonuses from the other classes. Prestige classes give no additional benefits to defenses and attacks.

Monsters and animals count their HD as levels for defence and attack progression. Most animals should get +1 Fort & Ref, while small creatures may get +2 Ref and big monsters +2 Fort. Outsiders and undead have +1 to all saves. Every character gets an extra attack every fifth level, starting from 5. These attacks have the usual attack penalties of extra attacks in d20 (i.e. a level 5 character has one attack with his normal bonus and another at -5).

Class Fort Ref Will Notes
Bandit +1 +1 - +1 dodge
Barbarian +1 +1 - +1 dodge
Borderer +1 +1 +1
Martial Disciple +1 +1 +1
Noble +1 - +1
Nomad +1 +1 -
Pirate +1 +1 - Seamanship bonus adds to both attacks and dodge
Scholar - - +2 +1 Magic Attack
Soldier +2 - - +1 to attacks, +1 parry
Temptress - +1 +1
Thief - +2 -

Code of Honor grants +2 to Will, +4 vs Corruption. Faith gives +1 to Will.

Hit Points

Characters receive HPs worth full class HD + Constitution score from the first level. This means that a Soldier with Con 18 will get 28 HP at the first level. Further levels grant 1/2 HD + Con modifier up to level 10 (9 HP per level for a Soldier with Con 18). Levels after 10 grant +1,+2,+3 to hit points according to the Atlantean Edition rules. This rule applies only to humanoids and common animals. Monsters are not limited by 10 HD rule!


Certain skills have decided to marry and form a happy union. Balance + Escape Artist + Tumble = Acrobatics. Climb + Jump = Athletics. Disable Device + Open Locks = Mechanics. Hide + Move Silently = Stealth. Listen + Spot = Perception. Bluff has brutally murdered, cooked and devoured Disguise. Forgery is now a Craft skill. Someone hanged Use Rope. Acrobatics can’t be used for escaping Grapple, but one can use Dex as a base for an escape check instead of Str. (It would be too easy to get extremely high Grapple escape check.)

New skill: Knowledge (Demonology)

This is knowledge for fell sorcerers and madmen about things from Beyond. It can be used to identify demons, know stuff about Mythos and so forth. It gives far more accurate and detailed information than Knowledge (Arcana). However, the more you know, the more susceptible you become to the Corrupting effect of those same forces. Every three ranks in this knowledge grants -1 penalty to Corruption and insanity saves.

Thieves have their skill point gain reduced to six per level, since many of their class skills have been merget. They still profit from the change, perhaps encouraging some cross-class skill picks.

Healing wounds works a bit differently. Heal check to treat a wound so it doesn’t get infected is DC 15. In addition, first aid heals the character as the skill check -15. So a Heal result of 30 will recover 15 hit points. A second check can be made as long-term treatment.

No synergies, they are too messy.

Feats & Sorcery

MAB requirements for feats, spells and prestige classes are now requirement x 2 = level. In other words, Dread Serpent (Prerequisite: MAB +4) now requires eight character class levels or monster HD. Any class will do, so Scholar 2/Barbarian 4 may gain access to spells that require MAB +3 or six levels in Acheronian Edition.

All classes except Scholar count as a half caster level – Scholar 2/Barbarian 4 has four caster levels in regards to spell effects.(Scholar levels provide full caster level.)

BAB requirements are replaced with an equal level requirement. For example, Improved Critical requires BAB +8. In the Acheronian Edition this converts to eight character levels regardless of a class.

Dabblers may select any Sorcery Style that does not require other Sorcery Styles as a requirement. Thus Immortality and Cosmic Sorcery, for example, are not available for a Dabbler, but Summonings and Necromancy are. Sorcery is available once per week, not once per month.

New feat: Student of Sorcery

Requires: Dabbler or one or more Sorcery Styles
If a Dabbler takes Student of Sorcery, he gains a basic spell in the type of sorcery he dabbles in. Effectively, he has gained access to the Sorcery Style and may learn further spells from it through other means. (Sorcerous tomes, demonic instruction, feats and Scholar levels.) If a proper sorcerer takes this feat, he gains one Advanced Spell.

New feat: Sorcerous Training

Requires: Student of Sorcery
Taking this feat grants the character access to an additional Sorcery Style, immediately granting the basic spell. This feat can be taken multiple times to gain access in several extra styles.

Master Alchemist

This feat is based on the Savant variant of the Scholar class. Scholar may take either Knowledge is Power or Master Alchemist on the first level. MA allows the character to choose 1 + Int modifier alchemical recipes. He may then produce them at half the usual cost. A Scholar that has chosen KiP may take MA with a feat or the other way around.

Power Attack & Magic Power Attack

The limit for both is character level / 2. (Max -5 to hit with PA on level 10 and so forth.)


Bluff check is taken as an opposed roll versus level / 2 + Sense Motive. So if a thief tries to feint a second level Soldier, he rolls against the bluff check result with 2 + Wis + Sense Motive ranks.

Ranged Finesse

All ranged attack automatically use Finesse as per melee rules with no feat required. Ranged Finesse only works in point-blank range (30 feet). If the target is concealed from the attacker, Ranged finesse can not be used.

Greater Mobility

A character with Greater Mobility may move up to his normal speed as part of a full attack action rather than merely taking a five-foot step. He may move and attack in any order, so he might for example move five feet, attack once, move ten feet, attack twice more and then move again for the remaining fifteen feet of his movement. Greater Mobility does not apply if the character is using any armor at all.

Improved Mobility

A character with Improved Mobility never provokes attacks of opportunity so long as he moves at least 10 feet during that combat round. Note that improved mobility does not apply if the character is using heavier than light armor.

Intricate Swordplay

Parry bonus gained from Intricate Swordplay does not stack with shields. Shields still grant dodge bonus against missiles, if a character with the feat chooses to carry one.

Critical Hits & Massive Damage

We use Paizo critical hit card deck. Critical hits are handled as per the deck.

Failed Fort save after Massive Damage results in a critical hit as per a critical with the attack that caused MD. Results of this critical card may not cause a new MD, no matter how much damage it inflicts. If a normal critical hit causes a Massive Damage and the save is failed, the victim suffers additional hurt worth the attacks maximum damage. (20 + modifiers for a greatsword etc.) This additional damage may not cause a new MD. Touch spells and alchemical bombs may score magical criticals from the critical deck.

Hero Points & Fate Points

Four classic uses for Fate Points – Left for Dead, Destiny, Might Blow and curing Corruption. These work according to Atlantean Edition. Fate Points are received only for great heroics, reaching major goals and surviving against incredible odds.

In addition, every character has one Hero Point per game session or scene or one week of downtime. Thus if two thieves go to rob tombs at two nights in a row, they have one Hero Point during each robbery. If an alchemist spends four weeks in a laboratory, he has one Hero Point per week. GM may allow players recover used Hero Points at whim when they seem to need an edge and deserve it. Hero Points can be used for following purposes:

  • Gain immediately +5 to Dodge and Parry for one round
  • Reroll one d20 roll, such as an attack roll, initiative, skill check or save
  • Immediately recover hit points equal to Constitution score
  • Ignore Terror of the Unknown
  • “Reset” Dabbler, allowing another use of sorcery
  • “Reset” demonic pact or other once per day/week power, allowing another use

Minor Tweaks

Crossbows have AP 6 and do 2d8 damage. Arbalests have AP 10 and do 2d10 damage. Both are simple weapons.

No arcane spell failure for wearing armor.

No High Living rule enforced.

Followers gained through Leadership can be “spent” to gain followers of higher level in 3-to-1 conversion. For example, three first level followers can be “converted” to a one second level follower. Converting first level followers in to level four followers would thus cost a lot as the multipliers stack. It should still be possible if the player wants a small elite group of henchmen rather than a horde of peasants as his entourage.

Thief gains Sneak Attack dice every third level, starting from first. (1 – 3 – 6 – 9 etc.)

The following spells have been altered:

Astrological Prediction can give an insight bonus of between +1 and +5, with the bonus increasing by one for every five points exceeded on the Knowledge (Arcana) roll, past 15.

Darting Serpent can be cast at one power point per caster level, otherwise unchanged.

Horoscope has been made more compatible with the fate point rules in Acheronian Edition. Rather than gaining one fate point every time a prediction is met, the target gains one “virtual” fate point when the spell is triggered: That is, when the preconditions laid out at the casting of the spell are met.

Make Gate requires a roll of Knowledge: Arcana and a Knowledge: Geography roll (substituting Astrology for Geography when travelling beyond Earth); The Arcana DC is 10 plus five for every step on the pp cost table in the spell description, the other DC is 5 plus five for every step on the table. Also, each activation of the gate counts as a mighty spell.

Shapeshifter no longer gives the character either the physical statistics or the HD of the creature transformed into. Rather, it modifies the character’s own physical ability scores by the animal’s size modifier, plus small static modifiers based on the animal type. Furthermore, the caster must be intimately familiar with the type of animal changed into, ritually sacrificing one example should suffice for this. The caster gains the movement type and speed of the animal transformed into, and gains its natural weapons and senses (such as scent), but does not gain any special attacks (such as pounce, rend or the like)

Warrior’s Trance gives its attack bonuses to all melee weapons wielded by the sorcerer

Purpose of the Acheronian Edition

Repairing attack and defence progression is the single most important tweak. It accomplishes two things – first, characters who are at the same level can no longer hit each other trivially with every attack. Second, Power Attack is no longer the guaranteed way to defeat every opponent. Third, everyone has a chance to succeed in almost every save even without a natural 20. Together with hit point progression, massed amount of lower level NPCs are now a much greater threat. They endure more punishment and multiple attacker rule gives them significant bonuses to hit. Combat and adventure in general are more exciting at all levels.

Sorcery tweaks make it more possible for every character to learn a little sorcery if desirable. This makes it easier to build characters (NPCs and PCs) that can, for example, be pure Nobles but still have a Demonic Pact without a need for a third party sorcerer. Attack progression gives Dabblers a chance to succeed in, say, a random Counterspell against a real sorcerer. Pure Scholars will still always be better in sorcery than feat-based tricksters and multiclassed Scholars. Only Scholar levels provide more Power Points, multipliers for extra PPs, “free” spells and 1-to-1 caster levels.

Acheronian Edition Rules

Conan Acheronian Edition Warma