Summary
One-Punch Manis no different from many other superhero and science-fiction stories, with a healthy appreciation for the storytelling potential of the multiverse. The series has previously dived into the concept on varying levels, but typically no more than a glimpse in previous instances, including time travel and parallel realities. However, with the most terrifying and strongest attack seemingly threatening the fabric of the multiverse,One-Punch Manwill inevitably explore this sci-fi trope in greater detail soon.
One-Punch Man’smanga adaptation by Yusuke Murata has beautifully captured different renditions of the multiverse, stoking theories of fans for years at this point. It’s previously handled how timelines can be affected and altered, but now there’s a threat great enough to exist seemingly in the liminal spaces between these dimensions.

Empty Void, the latest major villain inOne-Punch Man, wields the Dimension Slash, the strongest attack in theOne-Punch Manseries so far,thanks to the foundation of the series' multiverse.
Dimension Slash Weaponizes the Multiverse in One-Punch Man
Empty Void Wields the Most Powerful Attack in the Series
Empty Void, the villain ofOne-Punch Man’sNinjas Arc, uses God’s powers to ignore the laws of reality combined with his gifts for dimensional travel, to fold reality into pocket dimensions before attacking them. This is known as the Dimension Slash inOne-Punch Man,most recently demonstrated in the redrawn version of chapter #200, where Void folds the series' home dimension to the size of a basketball before slashing it with his sword.Due to traveling “outside the universe’s causality,” Void can track down his target universe among the many that spring forth, as numerous as stars in the sky.
Empty Void, the villain ofOne-Punch Man’sNinjas Arc, uses God’s powers to ignore the laws of reality combined with his gifts for dimensional travel, to fold reality into pocket dimensions before attacking them.

The only other characters inOne-Punch Manwho can travel the multiverse between dimensions are Saitama and Blast, who eventually catches Void during his assault. Previously, Blast shows his dimension-hopping abilities in chapter #166, with Saitama copying Garou’s techniques to alter the timeline in chapter #168. But this momentary glimpse of the multiverse, resembling a sea of snowglobes, teasesthe diabolical potential if Void grows increasingly unhinged, channeling God’s powers to decimate entire dimensions inOne-Punch Man. However, it seems that Empty Void’s use of the Dimension Slash gives his position away, too.
Blast is the Best Counter to Empty Void’s Multiverse Attack
The #1 S-Class Hero in One-Punch Man Can Stop the Latest Villain
While Speed-o'-Sound Sonic and Flashy Flash hold their own against Empty Void, their enemy’s vast array of interdimensional warping abilities are still potentially too much for the pair. However, Blast is able to warp and seemingly follow Void’s trail and resist the temptation ofGod’s cubes, which, when in Void’s hands, have been able to entrance other characters by force. While Saitama is known to resist the cube’s temptations, whether he can resist it being forced upon him is undetermined, butBlast exerts even greater control over this multiverse-scale threat inOne-Punch Man.
Still, the most frightening prospects of this fight are likely to reveal themselves,especially with Void having God’s powers on his side. Conversely, Blast can travel between dimensions similarly to Void, mitigating an unfathomable threat to every reality in the multiverse inOne-Punch Man. Fans may have to wait especially long to find out how this will play out in theOne-Punch Manmanga, but with the Ninjas Arc, the multiverse not only plays a bigger part than ever, but it’s under threat from an especially maniacal villain.