C417 Time Reversal Machine.

"I'm afraid that even if the others have triggered such a hidden mission, they won't easily tell others. Moreover, completing such a hidden mission is not easy. To stop the birth of the Sentinel Robot, we have to go back in time. Ordinary people don't have the ability to travel back in time."

Thinking about this, Tian Yu smiled slightly, "But I'm different. Fortunately, I bought that thing