Ars Magica Definitive Edition (5th Edition rules, consolidated). Page refs are to the Definitive Edition (DE). Back to Ars Magica – Start Here.
The Core Roll
Characteristic + Ability + die ≥ Ease Factor → success. The margin tells you how well you did.
- Specialisation: +1 to the Ability when your specialisation applies.
- No score in an Ability? If it isn’t asterisked (*) you can roll it at 0, but with +3 botch dice. Asterisked Abilities (Latin, Lores, Medicine, Magic Theory, etc.) can’t be used at all without at least 1 xp.
- Rounding: unless a rule says otherwise, round down.
Dice
| Die | When | How it works |
|---|---|---|
| Simple die | No pressure | d10, 0 counts as 10. No botches. |
| Stress die | Danger, haste, combat, spellcasting under pressure | 1 = reroll and double (another 1 = ×4, and so on; zeros count as 10 on rerolls). 0 = roll botch dice: any 0 on them = botch (total is 0 and something bad happens); no 0s = die counts as 0. Other results = face value. |
Multiple 0s on the botch dice = a worse disaster. Three or more = about as bad as it gets.
Ease Factors
| EF | Difficulty | Rough feel |
|---|---|---|
| 0 | Trivial | Don’t roll |
| 3 | Simple | Untrained average person succeeds ~70% |
| 6 | Easy | Some skill → ~70%; skilled rarely fail |
| 9 | Average | Skilled ~70%, moderately skilled ~50% |
| 12 | Hard | Skilled fail about half the time |
| 15 | Very Hard | Very skilled + talented ~70% |
| 18 | Impressive | Top of the field ~50% |
| 21 | Remarkable | Masters succeed occasionally |
| 24+ | Almost impossible | Greatest masters, when lucky |
“Average” = Characteristic 0; “talented” = +3. “Moderate skill” = Ability 3, “skilled” = 6, “very skilled” = 9.
Botch Dice
| Botch dice | Chance of botch | Example |
|---|---|---|
| 1 | 1% | Default, good conditions |
| 2 | 1.9% | Running through undergrowth |
| 3 | 2.7% | Crumbling cliff in high wind |
| 4 | 3.4% | Fighting in driving rain, ankle-deep in water |
| 6 | 4.7% | Fighting faerie copies of yourself on an ice floe in a blizzard |
| 10 | 6.5% | Casting a spell in the Holy Sepulchre |
The chance can never exceed 10% (you must roll a 0 first). If you’d have time to try again, the SG shouldn’t call for botch dice at all.
Characteristics
Eight Characteristics, normally −3 to +3 (0 = average). They are fixed — only aging, drastic story events or powerful magic change them.
| Characteristic | Governs |
|---|---|
| Intelligence (Int) | Analysis, memory, academic work — paramount for Hermetic lab work |
| Perception (Per) | Noticing, intuition; Awareness, Hunt, Folk Ken |
| Presence (Pre) | Appearance, bearing, leadership, intimidation |
| Communication (Com) | Self-expression, persuasion, teaching and writing books |
| Strength (Str) | Physical power; melee damage |
| Stamina (Sta) | Endurance, will to live, soak — spellcasting relies on it |
| Dexterity (Dex) | Agility, fine control; Attack totals |
| Quickness (Qik) | Reflexes, Initiative, Defense (reduced by Encumbrance) |
Confidence (magi & companions only — grogs don’t have it)
- Start with Confidence Score 1 and 3 Confidence Points (Self-Confident: Score 2, 5 points).
- Spend after rolling, once you know the result: +3 per point, up to your Confidence Score on one roll.
- Can’t spend on a botch (you can on a non-botching 0), or on whole-season rolls (e.g., vis study).
- Spent points are gone for good.
Earning points — the SG awards 1 point at session end for each of: achieving a personal goal · contributing to a group goal · success in a difficult task (max 1/session) · entertaining roleplay · SG bonus (max 1/session). Expect 2–3 per session. You must have been played for a significant part of the session.
Personality Traits
A few traits rated −3 to +3 (Minor Personality Flaw → ±3; Major → ±6). For magi/companions they’re a roleplaying aid; for grogs they’re the guide to how the character behaves. Roll only when unsure: Trait + stress die vs EF.
| EF | Brave | Loyal |
|---|---|---|
| 0 | Barking dog | Loyalty = self-interest |
| 3 | Angry unarmed peasant (you’re armed) | Not denouncing the magi to a passing bishop |
| 6 | Apparently equal enemy | Standing by the covenant when threatened |
| 9 | Clearly superior enemy | Resisting a large bribe + protection |
| 12 | A dragon | Staying loyal under torture |
Players may change Personality Traits freely, but only between sessions.
Reputations
Someone has heard of you if stress die + Reputation ≥ EF:
| EF | Local | Ecclesiastical | Hermetic |
|---|---|---|---|
| 0 | Same village | Same parish/monastery | Same covenant |
| 6 | Same town | Same diocese | Same Tribunal |
| 9 | Same county | Same province | Entire Order |
| 12 | Same country | Whole Church | — |
A noteworthy public deed starts a Reputation at 1; further deeds are “xp” towards it, like an Ability.
Combat (DE p.393)
All combat rolls use stress dice. A round is about 6 seconds.
| Total | Formula |
|---|---|
| Initiative | Qik + Weapon Init − Encumbrance + stress die (rolled once per fight) |
| Initiative (casting spells) | Qik − Encumbrance + stress die |
| Attack | Dex + Combat Ability + Weapon Atk + stress die |
| Defense | Qik + Combat Ability + Weapon Dfn + stress die |
| Attack Advantage | Attack − Defense (≤0 = miss) |
| Damage | Str + Weapon Dam + Attack Advantage |
| Soak | Sta + Armor Protection (+ Form bonus for magi) |
Sequence: Roll Initiative once (ties reroll among themselves) → act in order, highest first (you may delay) → attacker rolls Attack, defender rolls Defense → if you hit, Damage − Soak, read the wound off the table → repeat.
Botched Defense = you are probably dead. Combat in Ars Magica is lethal — think before you wade in.
Damage Table (by Size)
| Size | Light | Medium | Heavy | Incapacitating | Dead |
|---|---|---|---|---|---|
| −2 | 1–3 | 4–6 | 7–9 | 10–12 | 13+ |
| −1 | 1–4 | 5–8 | 9–12 | 13–16 | 17+ |
| 0 (human) | 1–5 | 6–10 | 11–15 | 16–20 | 21+ |
| +1 | 1–6 | 7–12 | 13–18 | 19–24 | 25+ |
| +2 | 1–7 | 8–14 | 15–21 | 22–28 | 29+ |
Each band is 5 + Size points wide. (Size −4 or less: 1 / 2 / 3 / 4 / 5+.)
Combat Options
- Missiles: −3 to Attack per range increment beyond the first. Against missiles, only a shield’s Defense bonus counts (plus your Combat Ability for dodging).
- Mounted: + Ride score (max +3) to Attack and Defense.
- Exertion: spend a Fatigue level to add your Combat Ability again to one Attack, or to all Defenses until your next turn.
- Disengage: on your turn roll Defense instead of Attack; must beat every opponent who attacked you last round. +3 cumulative per repeat attempt.
- Special manoeuvres (usually Brawl): Trip Adv 3 · Grab worn item 6 · Disarm 9 · Take opponent’s weapon 12.
- Grapple: Brawl, free hands; Attack Advantage becomes Grapple Strength. Victim escapes by reducing it to 0 (inflicting a Light Wound on the grappler).
- Scuffle (knock-out fight): unarmed or sap = no penalty; real weapon −3 Attack and no weapon damage. Results: Light → 1 Fatigue · Medium → 2 · Heavy → 2 + Light Wound · Incap → 3 + Light Wound · Dead → 5 + Medium Wound.
- Magic in combat: one normal spell per round at your Qik-based Initiative, plus fast-cast spells (see Hermetic Magic Guide).
Groups & Shield Grogs
- Up to 6 combatants of similar ability (all totals within 5 points) fight as a group, using the vanguard’s stats; each member lands a blow when the group hits.
- Trained group (trained together for a season): leader coordinates up to their Leadership score in fighters; bonus = sum of others’ Combat Abilities, max 3 × leader’s Leadership, applied to Attack or Defense each round.
- Defenders: a character guarded by grogs can’t be hit until all defenders are down (or botch). Number defended ≤ number defending.
Weapons (selected)
| Weapon | Ability | Init | Atk | Dfn | Dam | Str | Load |
|---|---|---|---|---|---|---|---|
| Fist | Brawl | 0 | 0 | 0 | 0 | — | 0 |
| Dagger | Brawl | 0 | +2 | 0 | +3 | −3 | 0 |
| Axe | Single | +1 | +4 | 0 | +6 | 0 | 1 |
| Mace | Single | +1 | +3 | 0 | +8 | 0 | 2 |
| Short spear | Single | +2 | +2 | 0 | +5 | −1 | 1 |
| Short sword | Single | +1 | +3 | +1 | +5 | −1 | 1 |
| Long sword | Single | +2 | +4 | +1 | +6 | 0 | 1 |
| Buckler / Round / Heater shield | Single | 0 | 0 | +1 / +2 / +3 | 0 | −2 / −1 / 0 | 1 / 2 / 2 |
| Staff | Great | +2 | +3 | +3 | +2 | −1 | 2 |
| Long spear | Great | +3 | +3 | +1 | +7 | 0 | 3 |
| Pole axe | Great | +1 | +5 | 0 | +11 | +1 | 2 |
| Great sword | Great | +2 | +5 | +2 | +9 | +1 | 2 |
| Warhammer | Great | 0 | +6 | 0 | +12 | +2 | 3 |
| Short bow (15 paces) | Bow | −1 | +3 | 0 | +6 | −1 | 2 |
| Long bow (30 paces) | Bow | −2 | +4 | 0 | +8 | +2 | 2 |
| Javelin (10 paces) | Thrown | 0 | +2 | 0 | +5 | 0 | 1 |
| Sling (20 paces) | Thrown | −3 | +1 | 0 | +4 | −3 | 0 |
Weapon + shield: add the modifiers together. Full table DE p.400–401.
Armor
| Material | Partial Prot / Load | Full Prot / Load | Cost |
|---|---|---|---|
| Quilted / fur | 1 / 2 | — | Inexp. |
| Heavy leather | 2 / 3 | — | Inexp. |
| Metal-reinforced leather | 2 / 2 | 4 / 4 | Std. |
| Leather scale | 3 / 3 | 5 / 5 | Std. |
| Metal scale | 4 / 4 | 7 / 7 | Std. |
| Chain mail | 6 / 4 | 9 / 6 | Exp. |
Encumbrance
Add up the Load of weapons and armour → Burden:
| Total Load | 0 | 1 | 3 | 6 | 10 | 15 | 21 | 28 | 36 | 45 | 55 |
|---|---|---|---|---|---|---|---|---|---|---|---|
| Burden | 0 | 1 | 2 | 3 | 4 | 5 | 6 | 7 | 8 | 9 | 10 |
Encumbrance = Burden − Strength (if Str is positive; min 0). If Str ≤ 0, Encumbrance = Burden.
Encumbrance is subtracted from Initiative, athletics and spellcasting — but not from Attack/Defense if it comes mostly from weapons and armour.
Movement per round: Walk 10 + Qik − Enc paces · Hurry ×2 · Run ×4 (may need a Fatigue roll). One pace ≈ 3 feet.
Fatigue
| Level | Penalty | Recover to next level |
|---|---|---|
| Fresh | 0 | — |
| Winded | 0 | 2 minutes |
| Weary | −1 | 10 minutes |
| Tired | −3 | 30 minutes |
| Dazed | −5 | 60 minutes |
| Unconscious | — | 2 hours (+1 hour per extra level lost) |
- Short-term Fatigue: brief strenuous action → Sta − Encumbrance + stress die vs 6; fail = lose 1 level, botch = 2. Recovery needs quiet rest (doubled if active).
- Long-term Fatigue: all-day exertion, Ritual spells, forced marches. One level back per night’s sleep.
- Fatigue penalties apply to everything except Soak, and stack with Wound penalties. Hermetic magic can neverrestore Fatigue.
Wounds
| Wound | Penalty | Recovery interval | Stable EF | Improve EF |
|---|---|---|---|---|
| Light | −1 | 1 week | 4 | 10 |
| Medium | −3 | 1 month | 6 | 12 |
| Heavy | −5 | 1 season | 9 | 15 |
| Incapacitated | no actions | twice daily (sunrise & sunset) | — | — |
- Penalties from all wounds add together (no maximum). Soak is not an action, so no penalty applies to it.
- Recovery Total = Sta + medic’s Chirurgy (injuries) or Medicine (disease/poison) + magical aid + stress die. ≥ Improve EF → wound drops a level. ≥ Stable EF → stays, +3 to future rolls (cumulative). Below Stable → wound gets worse.
- Incapacitated: roll at sunrise and sunset. 0 or less = death. 9+ → all Incapacitating wounds become Heavy. Anything else → cumulative −1 to later rolls.
- Activities while hurt: −1/−2: travel and study normally, no strenuous action (including fatiguing spells). −3 to −5: walk slowly, half travel rate, study at reduced effect, no lab or craft work. −6 or worse: talk, eat, move short distances with help; no productive work. Overdoing it forces an immediate Recovery roll for your worst wound.
Other Perils (DE p.406–407)
- Non-combat damage: Damage bonus + stress die vs Soak + stress die.
- Heat & corrosion (per round, ×1 hand/foot · ×2 limb · ×3 half body · ×4 immersion): wood fire +5, boiling water +3, boiling oil +6, molten lead +9, molten iron +12, lye +3, quicklime +6, vitriol +9.
- Falling: +1 per 2 feet (double on hard ground, halve on soft). Collapsing wooden house +15; felled tree +18; collapsing stone building +21.
- Poison / disease: Stamina check vs EF; failure = a wound (heals via Medicine). Adder 6/Light · Arsenic 9/Medium · Monkshood 9/Heavy · Asp 9/Incapacitating.
- Deprivation: Stamina check each interval (air 30 sec, water 1 day, food 3 days), EF starts at 3 and rises 1 each time. Failure = lose a Fatigue level; once unconscious, wounds.
Travel
On foot ~20 miles/day · mounted courier 30 (urgent 50, fresh horses 100) · ship ~30. Large groups and carts are slower. Hurrying costs 1 long-term Fatigue level per day.
The Gift (for everyone who travels with a magus)
Ordinary people and animals react to a Gifted person as if they had a reputation for dishonesty and undeserved privilege. The Gift: −3 to all social rolls and totals (including teaching and training). Blatant Gift: −6, and people become actively hostile. Gifted characters can’t ride horses without magical help. An unGifted companion negotiating on their behalf takes no penalty — this is why companions matter. The Parma Magica blocks the effect between magi. Covenfolk get used to their magi, but not to strangers.
Magic at a Glance (magi)
Full detail in Hermetic Magic Guide.
- Casting Score = Technique + Form + Stamina − Encumbrance + Aura.
- Formulaic: Casting Score + die vs spell level. Meet it → no cost. Short by 1–10 → cast, lose 1 Fatigue. Short by 11+ → fails, lose 1 Fatigue.
- Spontaneous: Fatiguing = (Casting Score + stress die) ÷ 2, lose 1 Fatigue. Non-fatiguing = Casting Score ÷ 5.
- Penetration = Casting Total − spell level + Penetration bonus. Must exceed the target’s Magic Resistance.
- Magus Magic Resistance = Form score + 5 × Parma Magica (+ aura).
- Voice & gestures: Loud +1 / Firm 0 / Quiet −5 / Silent −10; Exaggerated +1 / Bold 0 / Subtle −2 / None −5.
- Botching a spell: 1 Warping Point per 0 on the botch dice; 2+ from one event → roll to avoid Wizard’s Twilight.
Aging
From the winter after you turn 35, roll every year: stress die (no botch) + age/10 (round up) − living conditions − Longevity Ritual. See Laboratory & Downtime Guide.
Source: Ars Magica Definitive Edition. Page references in each guide are to the Definitive Edition (DE). The Ars Magica 5th Edition text is released under CC BY-SA 4.0 by Atlas Games.
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