My Hero Academia depicts a future setting where Quirks are commonplace, and some Quirks are far more straightforward than others. Minor Quirks might give a person horns, fins or the ability to breathe fire or shoot lightning, while other Quirks are truly unique and raise many questions as to how they work. A good example of this is Mr. Compress' Quirk.
The League of Villains needs members whose Quirks are suitable for more than just combat, such as Dabi's Cremation Quirk. Tricky and deceitful Quirks such as Himiko Toga's are vital for villainy, and the same is true of Mr. Compress' Quirk, Compress. Only a few hard facts are known about this size-altering Quirk of his, although several more aspects to the Compress Quirk can be inferred from what the My Hero Academia anime has shown of it so far.
Is Mr. Compress' Quirk Factor Limited?
A person's ability to use their Quirk is based on their Quirk factor; if this is somehow lost, they cannot call upon that Quirk ever again. For many people, their Quirk factor is spread across the entire body, but some characters, such as Mr. Compress, are different. His Quirk factor is limited to his arms, and once he lost his left arm to Overhaul during their brief battle, his Quirk factor was reduced to just his right arm. Although Mr. Compress got a prosthetic left arm, that fake arm cannot use his Quirk.
How Flexible Is Mr. Compress' Quirk?
Many Quirks in the My Hero Academia universe have limits and conditions for their use, and these limits have in-universe explanations and are probably intended to balance the power levels. A number of Quirks can affect the physical properties of items but cannot be used on living matter, such as Mudman's Quirk. Similarly, Momo cannot make organic matter from her Creation Quirk. By contrast, Mr. Compress' Quirk can be used on living and nonliving items alike, with no clear limits at all. He has been seen compressing people such as Katsuki Bakugo, and he can also compress an entire car and release it later. He is free of the unofficial "you can't affect living things" rule of Quirks.
Mr. Compress Continues MHA Creator's Favorite Artistic Inclusion
It is clear by now that author Kohei Horikoshi greatly enjoys drawing human hands, and he factored hands into many of his MHA characters, such as Tomura Shigaraki being covered in hands or Izuku performing Smash attacks with his fists and fingers. Mr. Compress also relies greatly on his hands to fight, since his Compress Quirk only works when he touches the intended target with his hands. His Quirk factor may be contained in his arms, but hitting the target with his elbows or wrist won't count -- he must use his hands only. In theory, if he somehow lost his right hand, he would be rendered unable to use his Quirk at all, even if his right arm was intact from the wrist to the shoulder.
What Happens to Mr. Compress' Victims?
It's clear that when Mr. Compress uses his Quirk on a living being, usually a person, that target is placed in suspended animation. This prevents the victim from suffocating and dying while compressed, since they aren't getting any oxygen, and the target likely doesn't remember their time inside the "marble" item that represents their compression. When Mr. Compress revealed the compressed forms of Katsuki Bakugo and Fumkage Tokoyami, both boys were stationary inside their marbles, effectively frozen or put into suspended reanimation. In theory, Mr. Compress could keep a person suspended like that for years.
Does Mr. Compress Break The Laws Of Physics?
A variety of Quirks are supernatural, seemingly bending or even breaking the laws of physics at times. This is certainly true of Mr. Compress' Quirk, and not just because he can shrink objects down and restore their full size later. When Mr. Compress compresses an item or person, that object's weight is reduced as well, and Mr. Compress can easily hold the marbles between his fingers or carry them in his pocket.
According to its own name, the Compress Quirk simply squishes an item into a small size, but evidently, most of its matter is lost too, given that these marbles are so light. A 150-pound person affected by Compress won't become a 150-pound marble, for example. Even anime series such as Fullmetal Alchemist don't bend the laws of physics that severely -- Edward Elric would be shocked to see Mr. Compress warping the law of conservation of mass. The target's mass is temporarily gone, like true magic.
