Matthew, eighteen and fresh from high school, enters a world forever transformed by the emergence of gates and dungeons over the past 140 years. With humanity now wielding system-granted abilities, he's drawn into the perilous depths seeking glory and power. Yet fate has twisted his path—unable to choose his own class as he ascends through levels, Matthew must navigate an unpredictable journey where the system itself determines his destiny, forcing him to adapt to powers beyond his control in this dangerous adventure.