Episode 17

Metal Knight unloads missiles at Elder Centipede and cannot even mark the beast. Elsewhere, Garou appears to have beaten Metal Bat, though he grudgingly concedes the hero would have won with a single clean strike. Metal Bat rises and almost finishes Garou from behind, halting only when his little sister Zenko appears. When Garou retaliates, Zenko steps between the two fighters and forces a stop, holding her brother to his vow never to be violent around her. Softhearted toward children, Garou backs off and leaves to hunt Watchdog Man, and Metal Bat soon collapses from the punishment of both duels. Pineapple and Mohican, carrying the unconscious Narinki and Waganma, are crushed in short order by Rhino Wrestler, who seizes Waganma.

Sludge Jellyfish slithers toward Zenko to take a hostage but is scattered by Garou. Phoenix Man calls a truce and, alongside the others, tries to talk Garou into the Monster Association, which he flatly rejects. Promising a future reunion, Phoenix Man orders the monsters to withdraw, with Metal Knight latching onto Elder Centipede to trail them. Bang and Bomb, hunting Garou, cross paths with Fist Fight Djinn, whom Bang kills in a burst of frustration. A wave of monsters of assorted disaster levels, among them Marshall Gorilla, Do-S, Hundred-Eyes Octopus, Pureblood, and Maiko Plasma, strikes heroes everywhere and rattles the Hero Association. As Do-S prepares to finish Dynamite Man using her mind-controlled slaves, Fubuki intervenes. Over at the Super Fight arena, Saitama meets Bakuzan, Suiryu, Lightning Max, Lin Lin, Hamukichi, Choze, Zakos, and Sneck while Genos watches from the stands. Suiryu senses Bakuzan's hostility, wants only the prize money, and wishes he could have faced the fighter he knew as Wolfman. After Lightning Max downs Lin Lin, Zakos explains that competitors are matched by perceived strength, so Saitama concludes Zakos must be feeble for drawing him, which enrages the man. In the closing tag, Saitama ends the bout with a single dismissive slap, and Suiryu grows eager to meet him in the final.

Garou spares Metal Bat because of Zenko, exposing his weakness for children, and refuses Phoenix Man's recruitment pitch. Waganma is captured by Rhino Wrestler. The Monster Association pulls back with Metal Knight covertly tailing Elder Centipede. A synchronized monster offensive stretches the Hero Association thin, and Fubuki halts Do-S before she can finish Dynamite Man. In the tournament bracket, Saitama disposes of Zakos in one motion, setting a collision course with Suiryu.

Titled The Martial Arts Tournament, the episode belongs to the Monster Raid Arc and adapts material from chapters 58 through 61. It first aired in Japan on May 7, 2019, with the English broadcast following on November 9, 2019. The opening theme is Seijaku no Apostle and the ending is Chizu ga Nakute mo Modoru Kara. The adaptation trims several beats, keeping Metal Knight airborne throughout its clash with Elder Centipede, reordering the moment Zenko knocks out Metal Bat, and shortening Do-S enslaving the heroes in favor of other defeats.