Season 3
Saitama is a hero who only became a hero for fun. After three years of "special training," he’s become so strong that he's practically invincible. In fact, he's too strong—even his mightiest opponents are taken out with a single punch. Alongside Genos, his faithful disciple, Saitama performs his official hero duties as a member of the Hero Association. One day, monsters claiming to be from the Monster Association suddenly appeared, taking a child of Hero Association executive hostage. The S-class heroes gather and plan a raid on the Monster Association hideout to rescue the hostage. Meanwhile, Garou, a "human monster" who was taken by the Monster Association during a battle with the heroes, awakens in the Monster Association hideout.
Episodes
1. Strategy Meeting
The heroes plan a rescue of a child kidnapped by monsters, while Garou awakens deep underground.
2. Monster Traits
On his way to hunt heroes, Garou dines and dashes at a restaurant, but is chased by Saitama.
3. Organism Limits
Garou fights Insect God and King the Ripper, while Tareo gets kidnapped. Dr. Kuseno visits Saitama.
4. Counterattack Signal
The heroes prepare for battle without Silverfang and Genos. Garou attacks the Monster Association.
5. Monster King
The S-class heroes race to rescue a child hostage as Garou awakens in the Monster Association’s lair.
6. Motley Heroes
Class-S heroes plan the Monster Association assault, but Amai Mask arrives and clashes with them.
7. Counterstrike
Heroes arrive in Z City but face a monster ambush. A-class aids while Gyoro-Gyoro watches the fight.
8. Ninja Tale
Tempest Wind and Hellfire Flame, who were ninjas but are now monsters, battle with Flashy Flash.
9. Brave Child
Child Emperor finds Waganma and faces Phoenix Man, using his ultimate weapon to protect him.
10. Immortal Bloodbath
No overview available.
11. Episode 11
No overview available.
12. Episode 12
No overview available.