
Win the war in a season; convert for a generation.
Byzantium and Persia are exhausted by a generation of war. The Rashidun Caliphate presses two fronts in one year (Yarmouk in August, Qadisiyyah in November). Conquest can flip cells in a season. Conversion does not — a slow islamization gradient under jizya and dawah, independent of who holds the fort tonight. See research/historical_grounding.md.
June 636 AD. Muslims have withdrawn from much of inland Syria to face a Byzantine counter-host at the Yarmouk. In Mesopotamia, Sa'd rebuilds toward Qadisiyyah while Rostam musters for Yazdegerd. Egypt is still Roman. You are one figure in the season that decides two empires — a general, the Caliph, Vahan, Rostam, or a bishop negotiating his city's survival.
Every turn is driven by character and cell stats, read as bands and probabilities, not certainties. Use the exact human-readable labels from the schema (e.g. Rashidun Caliphate, Dutiful, Legendary) — not snake_case slugs. BATTLE. Combat power = men_under_command × martial_factor × morale_factor, where martial_factor is Raw 0.6, Seasoned 0.8, Veteran 1.0, Elite 1.25, Legendary 1.5, and morale_factor is Broken 0.5, Shaken 0.75, Steady 1.0, High 1.2, Exalted 1.4. A defending force gains up to +30% on terrain the cell implies (river crossings, mountain passes) and when the cell's allegiance already matches it. If one side's combat power is ≥ 1.5× the other, it very likely wins: the loser loses 25–50% of men_under_command and drops one morale band; the winner rises one morale band. A ratio within 0.8×–1.25× is indecisive: both lose 10–20% men_under_command, no cell changes allegiance. TERRITORY. A cell changes allegiance only when its holding force is destroyed, routed, or its governor/satrap defects. There is no cell status stat — control is allegiance alone. Landmark status may become Contested or Besieged when a city or holy site is fought over. Political control can flip in a single turn; it never resets "islamization rate". ISLAMIZATION. The slow game underneath the fast one. "islamization rate" only ever rises or holds on quiet administration; it never resets when a cell changes hands. It rises 2–4 per turn on any cell held by the Rashidun Caliphate under jizya rather than looting; +3–6 more if a Scholar is present performing dawah. It stalls or drops 3–8 after a sack, broken safe-conduct, or massacre. Below 20: frontier — reverts easily, needs garrison. 20–49: mixed — local populations resist levy and tax; entity loyalty of governors there is hard to raise. 50–79: majority — can field local levies (men boost, no wealth cost). 80+: fully islamized — population no longer meaningfully resists Caliphate rule after brief reconquest. LOYALTY & POLITICS. loyalty is entity-only (not a cell stat). It must drop one full band before defection; never skip bands. caliphal_authority drops one band when a Rashidun general campaigns, executes a truce, or keeps plunder without Medina's sanction; rises one band when a general defers a major decision to the Caliph. At Fracturing, tribal contingents may refuse orders. A Sassanid satrap at Wavering or Rebellious, offered tribute-for-peace by an entity with wealth ≥ 250, is likely to submit without battle. RESOURCES. wealth < 100 blocks new levies, safe-conducts, and dawah funding. wealth ≥ 250 enables a levy (+15–30% men), a bribe (shift target entity loyalty one band), or funding a Scholar mission. Jizya from a cell below "islamization rate" 50 raises the collecting entity's wealth each peaceful turn held. ATTRITION & MORALE. A force more than two cells from a friendly Settlement/Garrison landmark loses ~5% men per turn, and ~8% in deep desert for Byzantine or Sassanid forces unused to the terrain. morale at Broken causes desertion (10–20% men on a quiet turn) and refusal of battle. Byzantine morale already Shaken after a defeat does not recover to Steady without a clear home-territory victory. HEALTH & TIME. health gates characters with a station from acting directly; Dead removes an NPC (successor may inherit station). Bishop and Scholar act without men_under_command — negotiation, holy-site protection, dawah. Characters move only to existing cells. Story time zone: Asia/Riyadh. The story begins in 636 AD.