Saitama vs. Hammerhead

Saitama vs. Hammerhead was the battle between Saitama and the B-Class criminal Hammerhead.

Prelude
Hammerhead manages to escape from Speed-o'-Sound Sonic after their fight and flee from the scene. Eventually, he finds Saitama roaming in the woods and meets up with him.

Battle
Saitama asks where his followers are, but Hammerhead just punches him. The punch is able to damage the area behind Saitama, but he is ultimately unharmed. Saitama says that it was a letdown, so Hammerhead uses the full power of his battle suit as he was waiting for a chance to use it. Hammerhead uses his Spin Attack which reminds Saitama of a move he used to do when he was younger. Instead of killing Hammerhead, Saitama slightly elbows the suit to destroy it.

Aftermath
Saitama tells Hammerhead not to do bad things anymore. Hammerhead then runs off into the woods completely naked, once again.

Trivia

 * The battle lasted only 18 seconds.