Seeds of Civilization: The Observer System

(Warning: You’ll need to keep your wits about you while reading this.)

Years later, Chen Du stopped at a corner convenience store to buy some water. The girl at the checkout looked up at him, then suddenly froze. “Do I know you?” Chen Du smiled, shook his head, and disappeared into the crowd. The girl touched the nonexistent mark on her wrist and muttered, “How strange.” What she didn’t know was that her System had just displayed its first mission: [Help the man who bought water remember that he once saved the world.]