One-Punch Man: Giant Insect, Volume 11 (by Yusuke Murata)

Life gets pretty boring when you can beat the snot out of any villain with just one punch.Nothing about Saitama passes the eyeball test when it comes to superheroes, from his lifeless expression to his bald head to his unimpressive physique. However, this average-looking guy has a not-so-average problem-he just can't seem to find an opponent strong enough to take on!While Saitama's distracted at a martial arts tournament, Centichoro, a threat-level Dragon monster, attacks! Metal Bat engages it in battle but struggles against its gargantuan size. The monster knocks him into the distance and right into the path of hero-hunter Garo!