Eternal Life and Invincible Defense: How Will You Deal with This?

[Wild fantasy + Transmigration + Cunning protagonist + Brainless power fantasy. If that's not your thing, don't read!] Zhou Xingchen transmigrates to the Nine Desolate Domain. The Tianchen Sect refuses to take him as a disciple, so he kneels outside the sect for three days! During a thunderstorm, he awakens the Heavenly Punishment Puppet Immortality System! The System automatically matches him with the most powerful person nearby to complete the Host's missions! Puppet: Can I refuse? Zhou Xingchen: Go ahead and try! Heavenly lightning will strike you at once. Fail to complete the mission and you're erased! Puppet: I'll kill you! Zhou Xingchen: You can't kill me. I have invincible defense, and your attacks rebound at six times their strength! A puppet that turns on its master gets twice the heavenly punishment! Fail the mission and the puppet is erased! With immortality, invincible defense, and the strongest puppets at my side, how will you handle me? (It's a brainless power fantasy, so you don't have to think. Head straight to the main story!)