Saitama vs. Groribas and Geryuganshoop

Saitama vs. Groribas and Geryuganshoop are two battles that take place within the Dark Matter Thieves' ship.

Prelude
Shorly after the S-Class meeting and the invasion of the Dark Matter Thieves, Saitama invades and gets inside the Dark Matter Thieves' ship after punching a hole through it.

Battle
Geryuganshoop sends Groribas to prevent Saitama from damaging the ship any further. Groribas starts gloating about his abilities but is defeated quickly by a swift punch from Saitama.

Geryuganshoop than telepathically communicates with Saitama and warns him not to go any further into the ship. Instead, Saitama ignores this warning and does the opposite by continuing to destroy the ship. Eventually, Geryuganshoop encounters Saitama and claims himself as the top telekinetic in the universe. He starts sending large amounts of rubble at Saitama and believes he has won, but Saitama remains unharmed. Saitama remarks that throwing around rocks with telekinetic powers is a waste of power and anyone could do so. He then kills Geryuganshoop by flicking a pebble at his head and splitting him in half.

Aftermath
Saitama is unharmed and asks for directions to Boros's throne room. He will eventually encounter Boros, which will lead to the final battle within the ship.