Genos vs. Armored Gorilla

Genos vs Armored Gorilla is the battle between the future S-Class hero Genos and the Cyborg Mutant Armored Gorilla.

Prelude
After witnessing Saitama defeat Mosquito Girl, Dr. Genus becomes interested in Saitama's power and sends some of his creations to retrieve him. After Genos goes to Saitama's apartment, one of Dr. Genus's creations, Kamakyuri, busts threw Saitama's roof and is swiftly killed by a ticked off Saitama. Outside Genos encounters Armored Gorilla and fights him.

Battle
Armored Gorilla attacks Genos, but misses and Genos counters with a kick, before jumping back and charging. Armored Gorilla tries to swat him, but is blocked. It then shows Armored Gorilla charging at Genos, with Genos dodging and and performing a failed counter with his incineration cannon which doesn't effect Armored Gorilla at all. The final scene shows Armored Gorilla defeated by Genos.

Aftermath
After this battle, Saitama and Genos are told about Dr. Genus and the House of Evolution. Saitama then decides to go there right away because he thought there was a sale the next day. Before leaving, Genos asks Armored Gorilla about the House of evolution's cyborgs in an attempt to find more information about the cyborg that destroyed his town as a child.