Summary
Chainsaw Man's Devil-erasing power is explained by Barem as a forgotten use of a chainsaw. The explanation of Chainsaw Man's power is very realistic and adds a lot of intrigue to its mechanics. How Chainsaw Man's power works will be fully revealed in the future.
Warning: Contains spoilers for Chainsaw Man chap #170. One of the most mysterious aspects of Chainsaw Man always the main character's ultimate ability: the power to erase the Demons he consumes from history. The powers of Demons are usually just extensions of the fear they embody, however the Chainsaw Man seems to be an exception with powers completely separate from the specific fear of chainsaws.
The reason behind Chainsaw Man's powers has always been a mystery, but Chainsaw Man Part 2 finally addresses that. Chapter #170 continues from the previous part with Barem's sudden reappearance in front of Denji. Their conversation leads to Barem explains to Denji why Chainsaw Man can erase Devils from existence.
This reveal makes Chainsaw Man and Devils in general even scarier than before, and overall, it does a great job of adding to Chainsaw Man's overarching lore.
Chainsaw Man's Most Powerful Power Has a Surprisingly Simple Explanation
Explaining the mystery behind Chainsaw Man's power
In chapter #170 of Chainsaw Man, Barem explains to Denji that he needs Denji to return to the state he went through during the Control Devil arc, leading to Denji eventually learns that Chainsaw Man has the ability to erase any Demon he consumes from existence.. While fans and many characters in the series already knew this, this was the first Denji had heard of it, so he pointed out that chainsaws had nothing to do with such things.
Barem then explains what he believes is the logic behind Chainsaw Man's powers: The chainsaw was once used to wipe out Devils.But the Chainsaw Man wiped out so many Demons that people eventually forgot about it. The explanation for the Chainsaw Man's powers is simple in retrospect, and also very practical. In real life, countless tools and practices have uses far beyond their original purpose.
Incidentally, chainsaws were originally used as surgical tools before being used for tree felling and other outdoor activities. Given Tatsuki Fujimoto's creativity, it's not hard to imagine that he was inspired by this fact to create Chainsaw Man's powers. Making people forget that chainsaws have anything to do with killing Demons would be a completely simple explanation for this mystery.
Chainsaw Man's Power Explained Makes Devils Even Scarier
Obviously, this is just Barem's theory, and it may not be true, but it would be strange if the author inserted it into the story without any real reason. It's also interesting to note that Chainsaw Man's power to wipe out Demons persists even after this use of the chainsaw is forgotten, meaning that Chainsaw Man's powers are not as related to the human world as the powers of other Demons. This is confirmed with the explanation that Chainsaw Man draws his power from the fear of Demons, in addition to humans.
Regardless of what the truth will be, it's clear that Fujimoto is holding back the explanation of the mystery of the Chainsaw Devil's powers for a pivotal moment in the series' future, as Chainsaw Man There's now more focus on Denji's emotional struggles, which is part of what makes the series interesting.