Joseon-equivalent monarchy with TWO aristocracies:
- Native yangban (land, bureaucracy, culture, conservative)
- Sino-Korean houses (ex-Song garrison, industry, military, pragmatic)
- King balances both — empowering one weakens the other

Economy: mining oligarchy (5-8 families), transitioning state→private ownership
- Chaebol precursors controlling iron/coal/gold/steel

Five gameplay pillars:
1. Belgian Dream: build navy + seek colony (small state escape route)
2. Jianzhou Problem: rival twin, logical ally but emotional enemy
3. Japan Wound: historical invasions + 独走 risk, impossible alliance choice
4. Song Black Hole: cultural gravity pulling Korea back into vassalage
5. Identity Project: forge Korean nation (한글, education reform, unified nationalism)

Flavor: hermit kingdom that opened, mining towns vs court culture,
de facto DMZ on Jianzhou border (smuggling, spies, tunnels)

Co-Authored-By: Claude Opus 4.6 (1M context) <noreply@anthropic.com>

Japan: Pacific industrial power (Tier 1.5), Jianzhou rivalry, Alaska/Kamchatka empire
- Core: catch up to Tier 1, Sakhalin dispute, Pacific expansion vs consolidation
- 150yr modernization legacy, fur empire declining, naval dominance

Korea: "Belgium of NE Asia", small industrial mining state
- Nationalized mining, squeezed between 3 powers, survival through balance
- Identity question: Korean vs Chinese-influenced vs independent nationalism

Jianzhou Republic: industrial city-state, oligarchic republic
- World's oldest industrial zone (400yr), porcupine deterrence strategy
- Arms dealer to everyone, Song reconquest threat, Sakhalin dispute with Japan

Mongol Khanate: vast, sparse, mineral-rich
- Resource curse vs resource blessing dilemma
- Multi-vector diplomacy between great powers
- Genghis Khan legitimacy, nomad vs miner cultural split

Co-Authored-By: Claude Opus 4.6 (1M context) <noreply@anthropic.com>