Volume 4 escalates the action with larger threats and introduces the swift and deadly Speed-o'-Sound Sonic. Sonic becomes obsessed with defeating Saitama after experiencing humiliation in battle, creating a recurring rivalry filled with comedic tension. Meanwhile, city-wide destruction increases as powerful monsters continue to appear. The Hero Association faces growing pressure to protect civilians and maintain order. Saitama, still underappreciated, continues defeating enemies effortlessly while others take the credit. The fights are bigger, faster, and more destructive, showcasing Murata’s exceptional artistic skill. Humor blends seamlessly with explosive combat, keeping readers fully engaged. The volume also explores how public perception shapes a hero’s reputation. Saitama’s quiet frustration adds depth to his character beyond just being invincible. Volume 4 successfully balances parody with genuine superhero excitement.