I Summon Overwatch in the Last Days

"Captain, there are too many zombies on the Western Front, we can't stand it anymore!" "It's a small matter, dragon, devour my enemies!" Countless zombies were swept into the air by the giant blue dragon, and blood rained down in an instant. "Captain, there are a lot of saliva monsters on the southern front, and the soldiers don't dare to show up!" "Noon has arrived!" At some point, countless tumbleweeds rolled over the city wall. Ten minutes after the gunshots were fired, there was no longer a zombie standing in front of them. "Captain, a huge zombie has appeared on the eastern front. Run away!" "There is no word escape in my dictionary! Dragon God's Sword, give me strength!" A flash of green light flashed, and the super giant zombie's head was cut off instantly, and it fell on its back. This is the story of a boy who activates the Overwatch system and fights in the end of the world. For the future of mankind, the world needs more heroes!