Included in the DVD/BD volumes of the anime are specials featuring original tales crafted by the series' creator, ONE. The initial special, 'Shinobiyori-sugiru Kage,' unfolds post Saitama's clash with Mosquito Girl, focusing on Genos as he doggedly shadows Saitama in a quest to unveil the mystery behind his unparalleled might. Amidst this, an enigmatic figure emerges harboring a deep-seated grudge against Saitama for a 'certain reason.' The subsequent specials are: 2: 'Hanashibeta-sugiru Deishi,' 3: 'Kojire-sugiru Ninja,' 4: 'Gouin-sugiru Bang,' 5: 'Iroiro Ari-sugiru Kyoudai,' and 6: 'Fukanou-sugiru Satsujin Jiken.'