Year 2020, Sirens invades Earth, most nations are surprised by this sudden apparition, but soon the Sirens started the war destroying everything.
An international alliance is made, every warship was now under one flag.
A massive battle is expected The First Sea War,but humanity losses with heavy casualties.
Nukes are being launched, a nuclear winter is expected.
Sirens are unstoppable, nations fall into chaos just Russia, European Union, China, Japan and America survives, but not for long.