The End Is Coming, I Built a Fortress and Became the Boss

[Apocalypse + zombies + system + no virgin + no heroine + no invincibility + fortress forces + upgrading and strengthening + chaos of order] The apocalypse is coming, and countless zombies appear in the real world. Qin Feng, who was protected by his ancestors, obtained the doomsday survival system. With the help of the system, he built a doomsday fortress to house survivors and survive the doomsday. As the system's building prompt appeared, Qin Feng immediately decided to build it! After the violent sound. "What?! Is this a fortress or a coffin?!" Are there only zombies in the apocalypse? Where did the zombies come from? Why does the world change? Qin Feng established a fortress organization to survive in the apocalypse, develop his own power, and explore the truth of the world!