Nuclear weaponry, invented as early as in 20th century, is now prohibited by all space conventions, and its production is extremely complicated and strongly classified. However, the biggest empires and states can break the ban, build the silos and fill them. Hidden under the ground, large halls with steel walls are the best place to store nuclear interplanetary missiles. Missiles with nuclear warheads are capable of destroying not only military defense facilities, but also peaceful industrial buildings, and all kinds of troops on the target planet (a random number or levels of all buildings, units and defense will be destroyed on impact).

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If your planet is attacked, enemy ships will be able to destroy the silo during combat, and if there's a missile that has been launched from the silo and still in flight, that missile loses its target and falls on a random planet in the solar system of destination or on a random planet of the solar system of start.