All For Luz
Just like in My Hero Academia, Logical Weaknesses are pretty much ubiquitous in this story, which repeatedly drives home the point that Quirks are physical abilities subject to the ordinary limits of the human body.
Luz Noceda
As powerful as Luz is, like any person or Quirk, she has weaknesses stemming from her Quirk and the ones that she's collected over the course of the story.- Her Quirk, All For One, has one in that, while it can take any single Quirk and seems to have no limit to how many Quirks it can take, Luz does have physical limits which the Quirk does nothing to mitigate - and it won't be long before she reaches the limit of his physical strength. One time she suffered a Heroic RRoD and nearly became Half the Man He Used to Be due to having too many powers in her and later had to offload more than half and it nearly happened again.
- She's shown repeatedly that while she's capable of stealing any Quirk she can get his hands on , for her Quirk to activate he needs to physically touch the 'true body' of the holder, so anybody who is fast and agile enough to avoid being grabbed by Luz, or is able to attack at range, will be able to avoid losing their Quirk. Luz, likewise, cannot steal a Quirk by touching anything the Quirk produces, such as Cody's Quirk from any fire produced, or steal Jonah's Quirk, if she's attacked by the Super Smoke constructs.
- The All For One power is incredibly good, but it doesn't come with a user manuals for the Quirks she steals. If Luz wants to be able to use individual Quirks to the level of their original users, she may have have to train with said Quirks like the real user did, and since he has so many Quirks, he's average at best with using any individual one. This is why Shigaraki recommends Boring, but Practical and Simple, yet Awesome powers like Super-Strength and Super-Toughness over Difficult, but Awesome powers like Jonah's Super Smoke, since she doesn't have the spare time to train it to decent level.
- Luz has to consciously activate most of her individual Quirks, as having them active all at the same time would be impractical. She still needs time to think about which Quirks she wants to activate and to what effect, as such blitzing her so quickly she has no time to think can prevent Luz from doing more than frantically spamming singular Quirks.
- Luz's All For One takes a few seconds to steal any Quirk. This means it can be interrupted or allow a counterattack, like when she tried to steal Riley's Quirk in their first fight and Millie was able to stop her.
- Luz's Power Parasite Quirk doesn't actually empower Quirks she takes. As such, despite the amount of power she has, she can still be overpowered. This drawback gets mostly resolved after her "Quirk Awakening".
- Luz's "Vine" Quirk being made up of real plants which are Weak to Fire.
- One of the powers Luz has is a Shock Absorption Quirk, which lets her survive some pretty powerful hits. But, like in the manga, it's Shock Absorption and not Shock Nullification, which means there's eventually a limit to how many impacts Luz can take, a limit that relentless attacks like from the Golden Guard eventually surpass.
- Also it can only protect against blunt forces. Its no real protection against cutting weapons and piercing attacks (like high calibre bullets), magic spells or extreme heat. Even her "Quirk Awakening", it doesn't prevent her skin being pierced.
- Another Quirk she possesses is Stamina Negation, it allows Luz to negate all stamina depletion. While she can never grow tired, this doesn’t make her The Sleepless, even after she "awakens" it. She may also never get physically exhausted anymore but she can still get mentally and emotionally drained.
- With Zero Gravity, Luz can experience symptoms of vertigo if she overuses it, especially on herself. After overusing her Quirk, Luz can get so nauseous that she'll end up vomiting. She's able to get around this by by using it in conjunction with Air Walk.
- At the end of the 5th Arc, she acquires the "Bomb Touch" Quirk. This allows Luz to blow up anyone or anything from the inside out, so long as she feels a deep hatred for them be it Irrational Hatred or justified, and so long as she comes into physical contact with them. Otherwise, its completely useless in a fight. This weakness is mostly resolved after her awakening.
Other Quirks
- While not a specific weakness, any Quirk relying on close-range combat or touching an opponent to work is limited by the users ability to get there first, like Riley or Derreck. In some cases this is a non-issue, but against clever opponents or those with long range or mobility focused quirks (like Luz) it often becomes a major problem.
- Arla Thatcher had the Repair and later Camila which allowed them to Heal Thyself and other living beings acting as The Medic. However, it can't bring the dead back to life, as former tried with one of her fallen teammates. It also offers no offensive capabilities whatsoever either leaving Camila completely helpless when Wittebane's Giant Mook attacks her.
- When All For One gained it in his world he discovered it could only heal wounds, not cure diseases. Meaning he couldn't get rid of Yoichi's various ailments.
- Cody Johnson had the Flame Quirk. One of its abilities allowed him to morph his body parts into fire to avoid attacks. However, it can't turn his whole body into fire, leaving at least one part of him vulnerable to attack, especially sneak attacks.
- Kennedy Jennkins' Quirk was Pain Assurance. His Quirk relied on the person’s understanding of pain. If the person Kennedy was going to attack understood that they were going to die, then Kennedy’s power would react to that, do the same amount of damage the person thought their attack was going to do, and put that damage into real life. However, its only deadly when the targets is Weak-Willed. Those that are confident in their defenses sustain little to no damage from his strikes.
- Jacob's Quirk was Forced Power Activation. Its perfect for times when others refused to use their powers but its useless for combative situations all on his own. Its likely this reason that Luz doesn't keep it and offloads it.
- Riley Stewardson, the original owner of the "Bomb Touch" Quirk has the same weakness as above, as well as another. If Riley is in the blast radius when her victim goes kaboom, she's not immune to suffering the full recoil, and can be injured herself, due to lacking Super-Toughness. This happened when she used it on her father and lost an eye in the process. She would've suffered full Facial Horror if it wasn't only for her brother who has a healing spit Quirk to save her.
- Jonah Smith's Smog allows him to turn into a dark mist and use it to attack, dodge hits and eat away at anything it comes across, like acid. The problem with it, however, is that it takes the user’s full concentration to be used, which is why All For One never used it when he was alive and had it, he recommends Luz to not bother stealing it either. Case in point, he became too terrified to phase through Luz's Finishing Stomp when his final gambit fails to put her down her.
- The Golden Guard, like Luz also has Super Regeneration, however, it does not come with a pain blocking quirk to act as a Required Secondary Power. This is why he prefers to avoid attacks instead of tanking them like Luz.
- Amity can use One For All to amplify her muscle strength, speed, and durability as a form of Magic Enhancement, much like Midoriya can. However, it still puts enormous strain on her body to go all out. At first, she literally can't use it at all without severely injuring herself, and even after years practice and training she can only use 10% at most safely and typically only 5%.
Other Examples
- A Non-Quirk example is Millie Ravenclaw. Being part of the Emperor's Coven means she has access to all forms of magic for her kind, making her one of Luz's toughest opponents she fought in the Human Realm. However, her physical strength and durability is about the same as a human being's, being the size of a 10-year girl means she can't do that much damage with her bare hands (Not helped by the fact Luz has Super-Toughness). All it takes is to land one strong punch from Luz to defeat her.
