Peak Emperor Forced to Restart by a Foundation Cultivator?!

Ten thousand years as a Great Emperor, and his cheat system finally arrives—with the most absurd quest imaginable. Qin Xuanfeng stares in disbelief: destroy a 'legendary clan' protected by a Foundation Establishment ancestor? Since when is Foundation Establishment legendary? But the system's ultimatum is clear: complete the mission or face erasure. Now the mightiest cultivator alive must descend from seclusion to hunt down bottom-tier clans, turning the entire Great Luo Domain upside down in the process.