Saitama vs. Speed-o'-Sound Sonic: Round Three

Saitama vs. Speed-o'-Sound Sonic: Round Three was the third fight between the B-Class hero Saitama and the ninja assassin Speed-o'-Sound Sonic.

Prologue
Genos vs. Speed-o'-Sound Sonic continues, and Sonic attacks Genos using Scattered Flash Slash. Unable to deal with Sonic's speed, Genos decides to blast the entire area with his Incineration Cannon in order to beat him. Before he can do so, he is knocked down by Saitama, who doesn't want his house to be damaged. Saitama scolds Genos for not having any reason to fight Sonic. Saitama then decides to fight Sonic seriously due to his persistence, to which Sonic gleefully replies that he will show his newly developed technique.

Battle
Sonic attacks Saitama with his ultimate technique: Ten Shadows Burial. Genos remarks that Sonic must have gone through harsh training to perform such a technique. Fubuki deduces that Sonic's combat skills are worthy of the S-Class and that naturally, a B-Class hero like Saitama shouldn't stand a chance against him. While preparing for the kill, Sonic thinks to himself that he always feels helpless against Saitama and that he must win, or else he will never be able to move on from this crippling mentality. Saitama bends his knees, widens his stance, and counters with his own super move: Serious Series - Serious Side Hops, creating an infinite amount of clones and starts moving forward with it, all the while causing tremendous shock-waves that easily destroy Sonic's clones, beating him and ending the battle effortlessly yet again.

Aftermath
Sonic then appears to be knocked out, which to Genos resembles death, but Sonic managed to instantly leave. Fubuki, seeing everything, claims Saitama to be too strong, and her obsession to make him join her group grown even further.