Yuki Yuna is a Hero-verse Strategy Guide

How to be OP in Yuki Yuna is a Hero

Local to City Scale:
There are two real sets of forces that need to be addressed separately at this scale; the vertex and the heroes.

The Vertex are malefic creatures created in the hateful zone outside reality that seek to destroy the Divine Tree Shinju. Even the weakest of them, so relatively weak and plentiful that they are called stardust. The stardust though they are strong enough to tank the greatest of human weapons including nuclear missiles are the fodder of the vertex creatures and can not pass dimensional barrier themselves.

However thousands of stardust can merge into stronger vertex which themselves can fuse and become even stronger starcluster vertex. These vertex can are massively stronger then Stardust, with one, the Scorpio Vertex capable of equaling an attack technique equal to 50 teratons, enough energy to destroy a country. Superior to any human technology, they are faster even then missiles capable of moving mach 25. The vertex are mindless creatures, manifestations of a greater will, and have an exposed soul known as their "core" which can be sealed away outside the universe.

Their enemies are the Heroes, girls given a part of the power of the Divine Shinju. With this power they are capable of fodderizing the stardust and fight evenly with the Vertex. They are also capable of sealing which they do together against the souls of the larger vertex. However their most notable power is what comes up most often with the Heroes in terms of vs debating

The Heroes are protected by fairies, manifestations of Shinju that generate autobarriers against any physical attack used against The Heroes. These shields are ludicrously strong to the point that unless they are fighting someone completely outside their range in power, the most that will happen to them is being knocked out. These shields have allowed 4 Heroes to tank having a sun thrown at them and allowed them to survive within a black hole. It has been suggested that nothing physically weaker then Shinju itself can kill them physically which would suggest even universal levels of physical force would not work on them. Similarly pretty much any physical hax would be unlikely to work against them including freezing, poison, matter/energy manipulation and so on.  Note this is how it works when Shinju is at full power, but for the purposes of this so as to not limit this to picking counters to the verse only at a certain time this is assuming a Full Power Shinju.

Most physical abilities are pretty useless against them unless it's so strong it's highly unlikely the character would be in the same tier as them. Fortunately for coming up with counters, the Heroes have seemingly little to no resistance to non-physical hax, which at this tier is probably going to be soul hax and mind hax and yes that's probably the abilities I would suggest are best suited to fighting this verse.

Mind hax is interesting here. You might think that mind hax would be useless against the vertexes since they are explicitly mindless and indeed most forms of mind hax probably wouldn't work against them. However there is one form of mind hax that I think would be especially strong here; possession. Possession, the ability to transfer oneself (any plane body above physical) into another's physical body would work very well against EITHER the Heroes or the Vertexes, and it would allow the usage of the really high defenses of the verse and give them as an advantage to the user. Possession is a tactic that will probably be used against every scale and is seeming the best general weapon to use against the verse.

This leads into my first counter pick

Nightmare Nurse from DC Comics. 

Nightmare Nurse might have lower speed and MASSIVELY lower stats, but her sheer haxes would make defeating the verse at this scale child's place for her. She can casually possess people as well as easily teleport meaning they would have a hard time pining her, especially given most of them are not exactly stealthy (the vertexes are giant for instance). Only Mimori Togo I would suggest would be able to ping her by sniping her from a massive distance. 

However that brings up the next point, Nightmare Nurse can regenerate from the Heroes memories of her, meaning it would be nigh-impossible for the Heroes to kill her. While there is memory manipulation in the verse, it's only possessed by the God Tier. The Heroes wouldn't even be able to lobotomize themselves as the fairies would auto protect even from their own strikes. Even if she can't, she has counter-magic abilities and could likely undo the magic of the heroes barriers. 

It helps that Nightmare Nurse's bombastic personality and illusion capacity would do a good job of deceiving the Heroes as to her position. Also given that Asa's scapels ignore durability and even harmed Pandora and the Children of Trigon, it's possible they would be able to penetrate through the fairies barriers.

She is also just massively more intelligent and crafty then the low scale members of Yuki Yuna verse. 

Let's say you want a counter that's more direct though. I still think soul manipulation and sealing would be probably really good options. There is another power that I think would be really strong, especially at this level which brings me to my next counter pick

Death from Darksiders.

Statwise, Death in his base scales to the base form of his brother War, who destroyed the giant Dark Tower requiring city levels of energy. His reaper form is beyond this even, being above the Nephillim Weapon Earth Reaver which was compared in power to the eruption of a volcano in power which would put Death at stronger then most of the people on this tier save for the Scorpio Vertex. His speed is not quite equal, though it's comparable enough as he scales to his sister Fury who moved comparable to a hypersonic laser. He can bolster his mobility with teleportation, portal creation, duplication, and time travel. 

Death as the Grim Reaper can steal souls and seal them away much more casually then the Heroes can do which would be a one shot kill against anyone here. 

Death also has another ability that would probably be very broken in verse that not even the Shinju or it's enemy gods can perform, that being necromancy. Death can revive the dead as ghouls to serve him. Considering that countless of stardust, which are biological entities, have died, that would allow him to create his own armies of ghoul vertex, in any combination he wants. It's possible he could revive even the fallen gods which would make him completely and utterly ridiculous above anyone in the verse. 

There's another option. While the Heroes have immunity practically speaking to being affected by physical haxes, that does not suggest that the counter can't use it on themselves or the environment. My next counter is 

Princess Kaguya from Inuyasha

Statwise, she fast enough to blitz Inuyasha who dodged lightning from distance calced at requiring supersonic to hypersonic speeds. She was also much superior to Toutousai who split the ground deep enough for magma to come forth, a feat requiring millions of tons of tnt.

Beyond that Princess Kaguya also has mastery over the 5 elements, together with which she can use inter-dimensional sealing which would be a one shot against any of the characters at this scale. 

Her real strength is in how impossible it would be for them to hit her. She can casually exist in another dimension and teleport which they would have seriously difficulty following. She can freeze time for an entire planet. It's unknown if the fairies could protect this, since it would also seem to affect non-physical entities, but even if it doesn't it means that any attacks that the Heroes try to throw at her would freeze in time. This ignores her actual defenses like creating a black hole that absorbs any attack thrown at her and throws it back at her enemies 5 times over or absorbing enemies outright, like she could to ALL life (including the actual fairies that protect the heroes, taking away their defenses).

The Yuki Yuna verse would have a lot of trouble just being able to tag Kaguya, even ignoring her barriers and regeneration. If you wanted to be really mean you could use Naraku who has even crazier defenses. 

Planetary Scale:

At this scale you have the Leo Vertex, the leader of the other vertexes, whose soul alone was the size of the Moon and who was stated to be able to destroy a planet. You also have the Heroes in their Mankai Form, where they are super boosted by drawing on a greater portion of the power of Shinju. Yuna in this form was able to destroy the Leo Vertex's Soul with a Hero Punch as well as travel it's radius in 5 seconds, requiring speeds over Mach 1,000. 

Other then that, most of the strengths and weaknesses of the verse are the same at this tier, though in the era when Shinju is weakened it is notable that Mankai Form has a time limit. 

The most notable additions is MHS speeds which allows for possession users with a higher speed limit. Such as 

M. Bison from Street Fighter.

While M. Bison's raw power is signifigantly below this scale, being "only" about city level, his speed from the same feat deriving power from Ryu in Street Fighter Alpha 3 traveled from space to ground rapidly requiring clear MHS speed. This speed would scale to their actual attacks which they move comparable too, and this was before M. Bison was being empowered by the Black Moons. 

M. Bison can bolster his mobility to be far above the Yuki Yuna verse fighters here, using a combination of teleportation and his relatively small size compared to Leo Vertex and Mankai Heroes allowing for easy avoidance of detection and attacks.

Beyond that M. Bison has powerful psionic abilities as his most iconic weapon. He could theoretically use his mind control to just control the verse's fighters. Even more notable he could use his possession ability to simply possess the Leo Vertex, stronger then any of the other Vertexes. This would make him a god tier of the verse, able to boost the Leo Vertex's already great power as a vertex with psycho power to a godly level. Given that the Greater Vertexes like the Leo Vertex are made out of thousands of tiny stardusts, it's possible he could sacrifice them to charge up more psycho power or he could forcibly use his mind control to force them to fuse with his vertex body. 

Another character with somewhat similar stats that I think would do even better here

would be Ghostfreak from Ben 10.

Ghostfreak is fast enough to blitz Upgrade, who previous was comparable to superior to Megawatt, creatures made of electricity, and has even higher reaction speed as he was able to react to a light gun. He is also strong enough at his peak was comparable to Fourarms who scales to the Great One whose shell could survive the explosion of a planet. Given the surface area this would be at least gigatons.

Ghostfreak has standard "ghostly" abilities like intangibility and invisiblity, which would make him nearly impossible for the verse at this scale to deal with. 

He can also use the possession strategy that was mentioned above.

However Ghostfreak has another very important thing to note. Most of the Yuki Yuna verse cosmos was destroyed completely, and is reduced to fire and darkness. Ghostfreak's powers increase based on the darkness there is around him. In the void of space he was raised to a new height of power. I do not know what the limit to this power is but it's possible in a complete void, a near universal area devoid of all stars in complete darkness his power would reach an even greater height. At the very least this means Ghostfreak would be at peak condition, possibly higher across the Yuki Yuna verse.

If you want to take this strategy even further I would recommend

Cthulhu from Demonbane. 

Just Cthulhu's revival would lifewipe the Earth, knocking out everyone not at this scale. He can then summon Dagons numbering thousands, each about as strong as a stardust to distract and destroy any possible reinforcements. Cthulhu has MHS reactions capable of reacting to the Mach 750 Demonbane. His true power is also stated to be planet level meaning his telekinetic might could easily crush the Leo Vertex.

Demonbane Cthulhu also has potent mind and soul hax, that would soul steal and drive insane any of the verse's attacks come within range, as his range is vastly above the Mankai Heroes range and is only equaled at this scale by Leo Vertex.

It's barriers and regen, enough to regen from bits of itself, would make it extremely hard to kill, even ignoring it's ability to teleport at will and reality warp on a planetary scale (like turning a planet into a planet of Demons). 

Universal Scale Threat:

At this scale there's only really 2 fighters generally. Divine Shinju, the tree that maintains the universe's existence and it's opponent, the unseen gods that create the vertex. As there is almost nothing known of them this will focus on Shinju.

Shinju is a universal entity for maintaining the universe. It is generally immobile but it's "reflexes" are fast enough to react to the Mankai Heroes, and so MHS will be used as the speed value.

Shinju has a number of powerful abilities. Time Stop, Precognition, Summoning (even across time), Memory Manipulation, Existence Erasure, and manipulation of the reality it maintains.

It's weaknesses are that it's power gradually wanes with time. In the initial age it did not even need Heroes to protect it. As time progressed, the heroes lost some of the vitality and the tree became weaker. Also it's roots are a weak point and are fragile enough to be capable of damaged by the Leo Vertex.

The Time Stop + Precognition requires some answer. Time Manipulation Resistance seems the obvious answer, however another answer might just be infiltration and stealth (as the Shinju's precog is never shown to be unlimited, only to notice when the large visible Vertexes are invading). One further answer is just attacking from out of it's range. Or if a character is clairvoyant and ageless, waiting the fight out might be a possibility, just by waiting for the tree to wither.

Or...one could use the general abilities proposed earlier, possession. This brings me to my first counter

World from Fosters Home for Imaginary Friends. 

World was able to create his own reality similar to the Shinju and is under the speed limit scaling from Wilt who has a hypersonic speed feat of digging a large escape tunnel from a prison (twice) along with a number of other events in at most a few hours.

World is an intangible consciousness which appears as a face. He can possess anything that does not have a face. You'll notice that the Shinju is a tree, and as such does not possess a face. This seems like it would be a pretty clear tactic. 

He is also not particularly noticeable and could probably sneak in while Shinju is not noticing, or even shrink himself as he did to the others to make himself even less suspicious. He likely has clairvoyance as despite being trapped inside his toybox and seeing it he was able to recreate Fosters including details about it. This means he would likely be able to see when the tree is weakened and attack to possess it then. 

The only flaw with this strategy is technically there was a very brief period of time in Yuki Yuna where the Shinju manifested as a human and did in fact have a face. During this brief window, World would probably not win as he has no resistance to time stop, although even then it's arguable whether Shinju could affect World.

Another potential counter to Shinju that is more Divine and possibly thematically fitting would be

Hades from Greek Mythology.

Hades at the very least scales to Hera who could travel from Troy to Olympus in the speed of a thought requiring at least speeds nearing MHS, let alone scaling him to his brother Zeus who could move at the speed of lightning. Hades was strong enough to be a major player in the Titanomachy, a war that shook even the boundless Primordials and was likely comparable to his brother Poseidon who could flood the endless Underworld.

Hades has an inter-universal range, able from the depths of the underworld to move the ground to snatch Persephone. There's no reason he couldn't command it to do so on the roots of Shinju. Hades can also summon massive amounts of beings including the Furies as well as commands, the oneiros (individual dreams) which is at least millions of individual beings whom could attack at the tree and Shinju has never shown summoning anywhere near as many beings to defend itself. This is without even necromancy which Hades also has and could use similarly as stated above.

Hades also has his helm of invisibility meaning that the Shinju would have no way of detecting Hades position other then possibly knowing when he's going to attack. It's likely he can even resist time stop as he and his brothers overthrew their father Kronos who commanded time. 

Hades also has the power to suspend souls between the realms, a far of astral sealing beyond the Yuki Yuna Verse's and could possibly seal the Shinju if wanted or could teleport Shinju into the underworld as he did to Apollo to trap it. 

Beyond that Hades, as a Greek God is undying and ageless and simply could wait for Shinju to wither, which would be surprisingly thematic a fight for these two specifically. 

There's one more character who I think would do even better though, as a pseudo combination of the above two strategies.

Mimi from Flip Flappers.

Mimi's raw power is not entirely known, though it's implied she could potentially end the unvierse in her final form. However what is known is that she has casual inter-universal range, able to exist in pure illusion, the mental universe and affect the physical universe at will with enough force that she could easily break the roots of Shinju. 

Her speed compares easily to Pre-Final Form Conona and Papika who were able to casually fight across an imaginary world, which would require speeds hypersonic to massively hypersonic. 

Mimi's time manipulation can counter Shinju's as a mere shard of her power was able to automatically set time back 24 hours. Mimi can also create dozens of alternate timeline duplicates of people with just a shard of her power, able to absolutely completely overwhelm Shinju's precog and defenders with many versions of her.

While it's possible Shinju could affect her as it could affect the mental plane as it can affect the mental plane as shown by its memory manipulation, it would have no knowledge of Mimi's location and again could be completely overwhelmed by Mimi's speed. 

Mimi could reality warp targeting Shinju's weak spot, even from another dimension where it can do nothing to her, or she could just possess her as she did to Cocona. It's also notable that her presence can kill people, and a tree is a biological lifeform that can die.

Finally Mimi has shown the ability to change the age of others as shown when she de-aged Papika. Theoretically she could age the Shinju, weakening it by withing it. 

And that's how to be OP in the Yuki Yuna is a Hero Verse.