A My Hero Academia OC of mine, Quirk: "20 Phases”, where every week, he possesses a different power from a pool of 20. The order of what he gets is fixed (what you see in the artwork) and after Week 20, his Quirk will always loop back to Week 1’s abilities and the cycle repeats. Some of these powers warrant more explanation than others, but I’ll go over each week:
Starting off each cycle is Q-Swap's neutral "blank slate" week where his energy can copy external properties, such as other elements or others' Quirks. While it's easier to use this on only one property, it is possible for him to copy multiple in smaller doses. And to be clear, it's his energy that does the mirroring before himself, so if he creates something like a barrier wall or even a projectile, that will be what absorbs--let's say, fire, rock, water, or whatever else is thrown his way.
Strictly speaking, 20 Phases only gives Q-Swap one superpower at a time, but Sample can be a small loophole that can give him either a preview or refresher on the variety he will be able to experience going forward, even with the given restrictions.
Since most of these powers are pretty self-explanatory, I will also use these as examples to explain the more recurring nuances of 20 Phases. For instance, the element Q-Swap wields can also resonate with his surroundings if they match his element. On Week 2, Q-Swap can grow stronger and healthier just from being near other plants, trees, or grass and the effects are mutually beneficial. Likewise, if he's working with other plant wielders like Kamui Woods or Vine, all three of them (himself included) will receive an elemental buff. Unfortunately this does also apply to opponents who share the same element as well.
While Q-Swap's Quirk does not influence his mind or heart in any way, the reverse can be true. Different elements may be amplified by different emotions. Intuitively, fire can easily be fueled by anger and ardor, but the better he can control his emotions, the stronger his control of his power.
The 20 Phases also have a passive influence on Q-Swap's local weather. On Week 4, his presence can increase the chances of rainfall, which will certainly amplify his scale, but there needs to be a nonzero chance of rain to begin with. If for whatever reason Q-Swap is in a hot and arid setting during Week 4, he's not any getting rain, let alone a Quirk buff.
Despite changing every week, Q-Swap will still embody his given element purely enough to also be immune or at least resistant to attacks of the same element. Week 5 will especially strengthen him and even boost his speed if he absorbs external lightning.
For all its variety, 20 Phases is still strictly an Emitter class Quirk. For Q-Swap, there is usually a balance between controlling his surroundings or generating elements from himself. However, for more solid and earthier elements, there is a greater emphasis or more limitations on the latter. On Week 6, Q-Swap will mostly focus on bending the earth around himself, which is already extremely powerful if he can reapply to same impact to other solid surfaces (like a pseudo-superhuman strength buff). But if he wants to manifest earth and stone himself, the best he can do is create rock armor, if only partially.
Most of the 20 Phases are better suited for combat, but a few such as Medicine are tailored to support roles. Week 7 is Q-Swap's healer week, which he can use to mend himself as needed as well as others. While Q-Swap cannot produce medicine in a chemical sense, he can replicate the effects of different treatments and control them. For offense (when necessary), Q-Swap will also be able to imitate relaxants that can numb or floor an opponent without inflicting serious injury. For the best practices, this week encourages Q-Swap to hit the books on life sciences, chemistry, and pharmacology.
One of the most obvious challenges of Q-Swap's Quirk is that for every 20-week cycle, he only has one week to hone each element. To stay within any league he makes, Q-Swap has to learn and practice as much as he can in very limited time spans, making every day a race against the clock and even seconds feel priceless.
That said, one of the most practical workarounds is to practice singular techniques that can apply to as many weeks as possible if not all. Q-Swap's most common handle of the elements is to spiral them, especially around his arms like coils, so that they can be used for melee attacks, parries, or even high pressure projectiles to be charged and launched.
Of course, this is only really applicable to more fluid or energy based elements, such as Wind, one of the easiest and most liberating for Q-Swap to wield. This combined with being able to levitate makes this one of Q-Swap's favorite weeks in every cycle.
At this point, I've touched on how all kinds of factors--physical, psychological, and environmental--can influence his Quirk or vice versa. Shadow presents a more unique and challenging example to Q-Swap's physical wellbeing, because on Week 9, he's much more of a night owl and more easily fatigued during the day. The strength of his umbrakinesis will reflect this.
One of the abilities he will access to this week using dark shadows as a portal to a black subspace he can navigate in and out of for both stealth and fast-travel. For this reason, he prefers nighttime missions on this week (tempting to resort to vigilantism as well).
The exact time when Q-Swap's Quirk changes Phases is in the precise midnight between Sunday and Monday, and it's instantaneous--no "cusp" nor gradual changes. As such, Week 10 forcibly pulls him out of the previous week's night owl inclinations, often leading to the bluest Mondays. However, this time, the daylight will benefit him and tremendously so (but of course).
When he's exposed to brightness this week, Q-Swap's overall stamina, defense, and physical wellbeing will be boosted, though if he tries to channel his power, it will mostly be defensive (like a Starman's invincibility). However, he can use this time to store up light energy in himself so that when it actually gets dark, he will be able to channel the most intense light, this time for offense.
Here's another break from the traditional elements and it's Q-Swap's equivalent of a physical or "Fighting type" attribute. He envisions the movements he wants to perform then sets his body to autopilot to enact that vision without fail, even if it's a stunt he's not usually accustomed to. This is applicable to martial arts (barehanded or armed), acrobatics, sports, or even just regular exercise. This Week is most ideal for physical training as opposed to risking a wrong move on the field (unless he has no choice but to take a chance). If he has to practice a technique, he can let Demo show him firsthand how it's done before practicing it on his own.
As important as it is for Q-Swap to stay as present as possible each week, some are ideal for long term preparations and benefits to the other weeks. On Week 12, he can control and manipulate all kinds of metal and alloys to shape weapons if he needs to, though it's more difficult to produce on his own without external metals.
Additionally, Q-Swap can also replicate different kinds of metal to form a defensive skin coating, but if he tries to manifest that on its own, it's usually from his body's own trace metals. Either way, this is a week he prefers to be as well armed as possible.
In case it's not a given, 20 Phases is a Quirk that operates on its own rules. It absolutely must use these 20 powers, follow this exact order, they must remain Q-Swap's, and no alterations are allowed. Any attempts to steal, block, transform, or alter Q-Swap's control (e.g. brainwashing/mind-altering) over these elements will result in his Quirk activating on its own and violently targeting who or whatever trying to adjust it. On weeks like the 13th, this Quirk can easily become a chaotic hazard that may not hurt Q-Swap himself, but will endanger others indiscriminately, even if it does have a target.
Even an attempt to enhance his Quirk that doesn't come from facets of his Quirk itself (such as response to weather or emotions) will trigger this violent counter. It's like 20 Phases has a mind of its own that will not tolerate any uninvited changes to Q-Swap's willful usage (besides its own "berserk" reprisal).
Another scenario that activates the 20 Phases’ autonomy is if Q-Swap is vastly surrounded by his matching element beyond how much he can normally control. If he’s in the middle of a desert on Week 14, the sand around him may act on its own and take whatever shape it wants to support him, including a clone of himself that shares his fighting style.
Weather and environmental factors are nothing new, but for the most part, Q-Swap can avoid anywhere that’s inconvenient for his Quirk. However, all 20 phases have a fair chance of catching all four seasons in due course. Seasonal changes outweigh his Quirk’s influence on the weather and unless he relocates, they will inevitably affect the strengths or weaknesses of certain phases.
If Week 15 takes place in a freezing cold winter, Q-Swap will be OP. But if he gets it in a scorching summer, he won’t want to leave his house at all. Unfortunately, hero duty may not excuse that which is why Q-Swap will always need to prepare supplemental devices and equipment to help him through incompatible weeks.
All this does it give him X-Ray vision, but Q-Swap likes to complement it with marksmanship. It's the only week where he is permitted to use a gun, but it has to be tailor made to work well with is Quirk. For sniping, his rifle would need to be able pierce through walls (i.e. like a laser beam) in order to capitalize on a see-through vision and the scope also has to compatible with the vision itself (even if he's wearing a mask). X-Ray vision couple with anatomical knowledge will also help fire precise but nonlethal shots if he wants to incapacitate criminals.
Of course, at closer range, he can just stick to simpler pistols or even throwing darts.
While the name implies "sound" (and does include it), it refers to all the bars he can see on a projected screen for different surrounding stats. It's an interface which he can control these metrics like sliders on a mixing board--whether it's sound volume, room temperature, weight of an object, or even people's strength/speed/stamina including his own. Of course, as powerful and influential as this is, Volume is support oriented and optimal for team enhancement.
This is easily the most difficult but rewarding for Q-Swap to master. By default his energy and output keep changing between disparate elements (e.g. flames turning into water, lightning turning into metal, etc.) so it can feel like chaotic and luck-based.
However, Q-Swap can control what elements he wants to conjure, transmute, and even fuse, but it will just require more focus and discipline than any of his other stages. If he can do it right, he’ll even able to create a fusion similar to Shoto’s Phosphor.
The second to last week of each 20 Phase cycle is an absolute nothing-burger. He’s basically Quirkless, but nothing in his life really happens either this week. Classes are whatever, no breaking news on TV, nothing between local heroes and villains either, and barely anyone notices Q-Swap’s presence.
If nothing else, this is one of the few weeks Q-Swap can relax from his extremely tight schedule and just be a human being.
For a Quirk so strictly tailored to time, there is no element more fitting for the Calendar Hero's ultimate week and it's practically his very own holiday vacation. Within each cycle, there may be a few liberating weeks here and there, but here is where Q-Swap brings out his most definitive and quintessential self, and he'll celebrate every last bit of it that he can.
To be clear, Week 20 does not give him the power to time travel, but he can pause or dilate time as well as warp to a dimension outside of time where he can review his experiences throughout the current 20-week cycle. Because guess what? The main merit of Week 20 is for Q-Swap to summon copies and projections of said experiences. They can take the form of his own duplicate performing a move, just the elemental attacks themselves, his allies and enemies, and even pocket dimensions based on where he's been this cycle! And these can even include what he experiences this week as well. The greater his power boosts, team synergies, and even his enemies are, the loftier his ammunition for this week.
As OP as Q-Swap is on this "holiday break", there are still restrictions and limitations. He only summon the exact movements, characters, and places as they were. Even if that includes all his prior elements, Q-Swap cannot manipulate or reshape them--only spawn the exact shapes and trajectories they already took when they exists. Moreover, he can only summon one copy of the same experience at a time. However, Q-Swap can combine orr rearrange who uses what move in which location in any way that he likes.
Lastly, because of the absolute rule where the 20 Phases has to loop and repeat its cycle, even time dilation is not something Q-Swap can abuse. Even if he does prolong Week 20 for a short while, sooner or later, he will have to enter a new Week 1.