Coming from a Hundred Years from Now, I Will Definitely Punch the Aliens!

In the year 97 of the Earth's Dark Age, the 18-year-old Cheng Tian, ​​who is about to go to the battlefield, obtains the system and will travel back in 10 days to the three years before the alien invasion, which is 100 years ago! This time I will return to 100 years ago with technology and system tasks to see how I will use the system to defeat aliens and lead the earth to the pinnacle of the universe! This novel and its characters are purely fictitious. Any similarity is purely coincidental and should not be imitated.