Document Eagle0 victory and defeat (#8440)

docs/eagle0pedia/astro.config.mjs

@@ -20,6 +20,7 @@ export default defineConfig({
               label: "Concepts",
               items: [
                 { label: "Game Concepts", slug: "concepts" },
+                { label: "Victory and Defeat", slug: "concepts/victory-and-defeat" },
                 { label: "Eagle Round Flow", slug: "concepts/eagle-round-flow" },
                 { label: "From Eagle to Shardok", slug: "concepts/eagle-to-shardok" },
                 { label: "Shardok Battles", slug: "concepts/shardok-battles" },

docs/eagle0pedia/src/content/docs/concepts/index.md

@@ -7,6 +7,7 @@ These pages explain how Eagle0's major systems fit together. Use them when you w
 
 ## Eagle
 
+- [Victory and defeat](victory-and-defeat/) explains the strategic objective, leadership succession, faction destruction, and how the game ends.
 - [Eagle round flow](eagle-round-flow/) explains how a strategic round advances, why actions are simultaneous, and when players see results.
 - [From Eagle to Shardok](eagle-to-shardok/) explains how strategic movement turns into tactical battles and how battle results return to Eagle.
 

docs/eagle0pedia/src/content/docs/concepts/victory-and-defeat/index.md

@@ -0,0 +1,62 @@
+---
+title: Victory and Defeat
+description: How factions win, survive leadership losses, and leave the game.
+---
+
+Eagle0 is a struggle to become the last surviving faction. The game ends when only one faction remains; that faction wins. If no factions remain, the game ends without a winner.
+
+## When a faction survives
+
+A faction remains in the game while it has both:
+
+- at least one faction leader; and
+- at least one ruled province or moving army.
+
+Losing a province is therefore serious, but it is not necessarily immediate defeat. An army already marching can keep a landless faction alive long enough to conquer somewhere else.
+
+## Losing your faction head
+
+The death of the faction head does not automatically destroy the faction. Another surviving faction leader succeeds them.
+
+If no faction leader is available but the faction still has a province or moving army, the strongest surviving vassal can rise to become both faction leader and faction head. The faction is destroyed only if no vassal can succeed.
+
+Creating additional leaders with **Swear Kinship** protects the faction against a sudden leadership loss. A candidate must belong to the faction, have at least 95 loyalty, and be with the faction head when the command is used.
+
+## How a faction is destroyed
+
+A faction is destroyed when either condition is true:
+
+1. It rules no provinces and has no moving armies.
+2. It has no faction leaders after the succession check.
+
+When a faction is destroyed:
+
+- its provinces become unruled;
+- its incoming armies are removed and their supplies remain at their destinations;
+- its heroes lose their faction assignment; and
+- diplomacy and outstanding offers involving it are removed.
+
+Those heroes are not necessarily killed. They may remain in the world in unaffiliated states and interact with surviving factions later.
+
+## Strategic implications
+
+- Keep a succession option by gaining another leader or maintaining a capable vassal.
+- Preserve at least one province or viable moving army.
+- Do not assume an enemy is eliminated merely because its last visible province falls; it may still have an army in motion.
+- Remember that conquest can release, capture, or displace heroes without destroying their former faction immediately.
+
+## Quick answers
+
+**Do I win a battle by killing the enemy faction head?**  
+Not automatically. Leadership succession may keep the faction alive.
+
+**Am I defeated as soon as I lose my last province?**  
+Not if your faction still has a moving army and a leader.
+
+**Can a faction with provinces survive after all its leaders die?**  
+Only if a surviving vassal can rise during the succession check.
+
+**How does the whole game end?**  
+The final surviving faction wins. If every faction is destroyed, there is no winner.
+
+For tactical battle victory rules, see [Shardok Victory Conditions](/concepts/shardok-victory-conditions/). For leadership roles, see [Heroes](/heroes/#faction-leaders) and [Factions](/factions/#leaders).

docs/eagle0pedia/src/content/docs/factions/index.md

@@ -88,6 +88,8 @@ A faction can have a focus province. The focus province helps direct [province o
 
 ## Faction Destruction
 
+For a player-oriented overview of winning, losing, and leadership succession, see [Victory and Defeat](/concepts/victory-and-defeat/).
+
 A faction is destroyed if either of these is true:
 
 - It has no ruled provinces and no moving armies.

docs/eagle0pedia/src/content/docs/index.md

@@ -7,6 +7,8 @@ Eagle0pedia is the in-game reference companion for Eagle0. The tutorial answers
 
 Eagle0 is a strategy game about factions, heroes, provinces, armies, diplomacy, and tactical battles. The broad strategic layer is **Eagle**: provinces produce food and gold, heroes lead factions or rule as vassals, armies march across the map, and diplomacy shapes the war. When armies clash, battles are resolved in **Shardok**, the tactical hex-based combat system.
 
+Your strategic goal is to become the last surviving faction. Start with [Victory and Defeat](concepts/victory-and-defeat/) to learn how factions win, survive leadership losses, and leave the game.
+
 Use these pages when you want a quick reference for commands, hero professions, faction leadership, province stats, or tactical battle options.
 
 ## Sections