The Last Legendary System

Benign Cross was granted a rare leveling-up system, the Legacy System, and his first mission was to stop the glitches infecting an entire realm. The only problem? It was his system that seemed to be full of glitches. As a former soldier, Benign accepted the mission without hesitation. To his surprise, every impossible mission somehow ended with absurd rewards... [Alert! Congratulations! You have slain an Ancient Dragon. Reward: Unique Skill Unlocked!] Benign stared at the dead lizard-man with terrible aim lying at his feet. “That can't be a dragon.” [Alert! A flock of beast-level phoenixes has been detected! Host, flee immediately or face certain death!] Benign looked up at the tiny birds circling overhead, a giant question mark hanging over his head. “You call those beast-level threats?” Later, while testing his newly unlocked skill, Benign noticed a young elf girl peeking from the clouds. [Alert! The aura of an Elf Empress has been detected! Host, immediately bow and acknowledge her as your master for boundless fortune!] Benign looked at the curious elf girl in silence, his expression stiffening. A world where reality is falling apart. A legendary system that keeps identifying the impossible. Benign was convinced the system had completely lost its mind. The system disagreed. After all... It had never once been wrong. — Description from novelcodex.org