Raining Missiles was an event added in the Event Update in Version 3.0.
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When it strikes the terrain, it deals a lot of damage to surroundings.

 This event is rare and may likely be common in Intensity 5.0. When this event is activated, the map has a red atmosphere, and all types of missiles will start spawning in the maps. This makes this event extremely dangerous, but is defineitely possible to survive.