In the Zombie Apocalypse, I Can Summon Shura Armor

[Shura Armor*Zombie Apocalypse*Harem*Decisive Killing*Not the Holy Mother*Mutation*Superpower] Lin Yang, a sophomore at a certain university, suddenly traveled through time while sleeping in class. Before he could sigh, zombies broke out in full force. Food is in urgent need! Water source is in emergency! Zombies block the door! But... Fortunately, the system arrived even though it was late! The starting reward is Shura Armor! What zombies? That's the experience value of walking!