A browser country simulation
Choose a starting country, or several. Each becomes a prime aggressor and they take turns. You can add more primes during play. With Allow multiple vassals off, each country has at most one vassal: the acting aggressor pressures the weakest neighbour it borders, and that neighbour joins the vassal chain. With it on, a country may hold several vassals at once: it first vassalizes every weaker neighbour, may steal a vassal from a weaker liege, and only then pressures its weakest bordering vassal before any weaker overseas vassal. Real-world dependencies start as vassals of their parent. If Vassals add to their liege's power is on, each vassal supports its liege by the share you set, in both vassal chain and vassal fan. A sea neighbour is skipped for a land neighbour that is still weaker than the aggressor and no more than twice the sea neighbour’s power. If the last aggressor is weaker than the country it must face, it is consumed by the one above it. A weaker neighbour whose defences outmatch the attacker can still be vassalized, but is not consumed while another move remains. If a liege then consumes that vassal anyway, its combined power is cut and returns over a few minutes. If a prime cannot overcome its neighbours, its weakest neighbour seizes primacy. Secure Prime blocks that: the prime seeks the closest country it can still consume, and retires if none remain. Choose overall power (economy, population, military, and technology) or military power before starting, and optionally change how much each source counts.
Relative weights, scaled to 100%. Overall uses GDP, PPP GDP, population, military power, and tech (R&D spending). Open Military mix to change how that military share is built. Military-only mode uses spending, armed forces, and population.
How military power is split for ranking. Offensive and defensive mixes below are used for deterrence, not combined power.
Striking power. Stronger defence blocks consume while the attacker has another move, even if overall power is higher. Vassalize is still allowed; with nothing else left, they consume anyway.
Holding power. Strong enough defense deters consume by an otherwise stronger aggressor until that aggressor has nothing else to do.
Who may hold vassals, whether vassals add power to their liege, how primes take turns, and how far a strike can reach.
Allow multiple vassals switches vassal chain and fan. Vassals add to their liege's power gives the liege a share of each vassal's power, in either mode; Vassal tribute sets that share. Stronger defences consume penalty cuts combined power when a liege eats a vassal whose defence beats its offence because nothing else remains; Stronger defences penalty is the cut, Penalty returns is how long the lost power takes to come back. Balance primes lets the weakest prime keep acting. Secure Prime stops a prime from being usurped or vassalized: if it cannot overcome its neighbours it seeks the closest country it can consume, then retires. Distance cuts striking power for targets that are not a practical neighbour. Ocean borders are treated as this many times harder than land. Sea range is how far a sea neighbour still counts as bordering. Spread consume paints the takeover from the border inward; turn it off for an instant recolour.