章 424: Chapter 209: Coffin Man_2

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The "3/3" figure indicated that the collection of Upgrade Essential Items necessary for the Drone Upgrade was complete. Upon seeing this number, Yan Fei finally let out a sigh of relief. The acquisition of the third Upgrade Essential Item hadn't taken long, but the process had been extremely difficult, definitely the most challenging of all his previous endeavors. Not only was he rendered helpless by the Laser Array inside the Museum, but the appearance of a person capable of controlling thunder and lightning also posed a great threat to him. If the Thunder and Lightning controller hadn't been preoccupied with defending the entire Holy See, distracted by the multitude of Missiles launched by Yan Fei and forced to destroy them out of necessity, Yan Fei would have been in grave danger. As soon as the controller of Thunder and Lightning could spare a hand and attack Yan Fei with full strength, Yan Fei would have undoubtedly met with certain death.