Encounter oracle

What this number is, and is not

It is a floor, not a forecast. The model fights to the last body: no terrain, no tricks, no talking, no torches thrown, nobody running. Cairn is a game about avoiding exactly that fight, so a real table will almost always do better than the number here. Treat it as the cost of a scene going badly with nobody getting clever.

• Modelled: the DEX save to act in round one, auto-hitting attacks, armour subtracted from every hit, overflow damage into STR, the STR save against critical damage, death at 0 STR, paired dice keeping the highest, blast hitting everyone, and enemy morale saves at the first casualty and at half losses.
• Magic and monster abilities are modelled — . A basilisk wards off attacks and petrifies, a banshee's wail takes out anyone who fails a WIL save, a troll gets back up, an owlbear tears armour off, and a party carrying a Sleep spellbook can read it — paying a slot of Fatigue to do so, which in a full pack costs them their HP. Each verdict lists what it simulated and what it could not.
• Still not modelled: retreat — the big one, since Cairn is a game about not having this fight — plus hirelings, detachments, terrain, healing between fights, and the Scars table firing mid-fight. Five creatures keep abilities the model cannot express, each with a stated reason (fire and poison immunities in a model with no damage types, a lich's retinue, a wight's permanent STR loss). Of Cairn's hundred spells, sixteen are simulated and thirteen more are combat-adjacent but too loosely specified to simulate; the remaining seventy-one are not for fighting at all, which is the truest thing this whole model has to say about Cairn's magic.
• The bands are ours, not Cairn's. Cairn publishes no difficulty scale. Inventing one that looked official would be a lie, so: routine is under a 12% chance of anyone going down, risky above it, deadly means a real chance of losing someone, lethal means the party is wiped at least a quarter of the time.
• "Delves survived" is our stand-in for levels. Cairn has none, and it puts magic entirely in objects — so a character's power is what they are carrying, and carrying is capped at ten slots. One delve advances both halves at once: loot found, and a coin-flip chance of a scar, which raises a maximum. Advancement saturates by about the third delve, after which a veteran is not accumulating but choosing what to leave behind.
• A full pack is modelled, and it is brutal. "Anyone carrying a full inventory is reduced to 0 HP" — so encumbrance is not flavour here, and there is a point where picking up one more shield makes a party measurably worse. See what a slot is worth.