Code No. 0719

China's shadow army, a force that does not exist. There is no serial number, no file, and their sacrifices are marked as "missing on duty." No one knows their names and achievements. "War Song" is the highest honor of this unit. After the first generation, no one was qualified for decades. In the year 214 of the Federation Era, sniper 0719 was ordered to go to the southeast region to perform a beheading mission, but unexpectedly discovered the cipher text left by his former field officer 0718. It turns out that 0718 had already used itself as bait and used his life to pave the way for those who came after him. He traveled alone through rainforests, swamps, and blizzards, fighting all the way from Indochina to offshore island countries, dismantling the transnational armed "Ring of Flame", destroying the intelligence network "Black Blood", and uncovering the truth about the defection and revenge of former Shadow Force members. After returning from the mission, he became the second "warrior song" in the army. After an anonymous postcard with "alive" written on it arrived, he quietly disappeared. Many years later, the third-generation warrior Ge received news from abroad: there was his postcard in the post office of Beacon Town.