Doomsday: M.A.D.

Doomsday: M.A.D. (Mutually Assured Destruction) is a nuclear strategy game: a 1v1 ICBM duel, a full war from DEFCON 5 to DEFCON 1, and a living world where nations are born, trade, arm themselves and go to war on their own.

THE DUEL Two nations share a generated map. Each one has a headquarters, silos, rocket batteries, missile defences, a radar and tank factories. Raze the enemy HQ or bring its population under 15% to win, and saturate their missile defences before the big strikes.

WAR MODE A crisis that builds from DEFCON 5 to DEFCON 1, each level clearing more weapons. Industry, oil and uranium, strategic sites to take, bases to build. Raise battalions, build tanks and artillery, send fighters, attack aircraft, bombers and drones, build a shipyard and its fleet: destroyers, cruisers, battleships, missile ships, submarines, carriers. Select and give orders with a finger. Or watch two AIs wage a full war.

THE LIVING WORLD Two to eight nations on untouched land, each with its own name, tongue and ruler. They found towns that grow district by district, live off their food, wood, ore, oil and uranium, govern with their ministers, lay railways, trade, make alliances, go through crises and fight real wars: mobilisation, fronts, trenches, supply, landings, war fleets, peace treaties. Their towns judge their rulers: leaders, uprisings, coups, revolutions, dynasties. Industrial, atomic and orbital eras; the bomb leaves dead land and a nuclear winter. Every system can be turned on or off in the rules of the world, and you choose which units, defences and weapons the nations may use. Watch, or play god: volcano, tsunami, meteor, found a nation, stir up a province, change a ruler's temper, ring for war or for peace.

• 16 weapons: tactical salvo, cluster munitions, napalm, thermobaric, hypersonic glider, ICBM, MIRV, bunker buster, neutron bomb, EMP, Tsar Bomba, tungsten rod, orbital beam, antimatter, black hole, tectonic quake. • Destruction you can read: blast fronts that knock buildings over, craters, districts on fire, flattened forests, sinking ships. • Nine maps (island, archipelago, valley, desert, arctic, continents, inner sea, thousand isles, coast and isles) in five sizes, up to 24 km across.

ECONOMY AND LOGISTICS Farms, sawmills, mines, oil wells and uranium mines on real deposits; steelworks, refineries, munitions and arms factories, enrichment plants: a nation that owns its production chain pays half price for its weapons, and one that loses it pays double. Trucks, warehouses, double-track railways with stations, viaducts and tunnels, shipping lines: blow up a bridge or sink a tanker and the goods are lost. A Logistics map shows what is well linked.

THE SOUND Real recorded sounds, air-raid sirens, blasts that arrive at the speed of sound, ambience that follows the camera and music that follows the tension. Best with headphones.

Plays offline. Free, with the Full Arsenal as a one-time purchase: neutron bomb, Tsar Bomba, antimatter, black hole and the other wildest weapons, for good.

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