Global Tower Defense: I Built a Billion-Strong Dark Legion

After transmigrating to a parallel world, Luo Xiu discovers that it is an age of dark upheaval! Humanity across the globe is building tower-defense walls to hold back invasions by hordes of dark creatures, including zombies, vampires, giant beasts, werewolves, and evil spirits! With the System, Luo Xiu rises to power, leading all of humanity in building defenses while summoning and forging a mighty dark army of his own. Smoke fills the air as the age comes under Luo Xiu's command…