How they compare: Unbreakable Dark (Magical Girl Lyrical Nanoha)

Unbreakable Dark is one of the strongest beings in the Nanoha Multiverse and is the villain of the video game "Magical Girl Lyrical Nanoha A's Portable: The Gears of Destiny". During the ancient Belken Era spanning long before the current day; a magical high tech empire called the Belkan Empire controlled numerous dimensions and created powerful weapons one being the Tome of the Purple Sky. The A.I. controlling the Tome of the Purple Sky, formerly a humanoid called Yuki Eberwein, called The Sovereign of Purple Sky was a gentle A.I. by nature and did not like that her sole purpose was to destroy. When a program was written to overwrite the Tome of the Purple Sky, she and the tome were sealed into a contaiment unit called the Tome of the Night Sky, later to be morphed into the Book of Darkness by the Tome of the Purple Sky's dark magic. 

The PSP Nanoha games take place in an alternate continuty where at the end of Nanoha As, Reinforce, the AI guiding the Tome of the Night Sky, was not deleted and so the darkness of the book of darkness, could return. This was the A.I. previously known as the Soveign of Purple Sky now known as Unbreakable Dark or U-D. U-D, psychologically damaged from having been treated as a weapon of mass destruction, acted defensive and preemptively attacked anyone who she detects as an enemy. 

 

Unbreakable Dark is easily one of the strongest beings in the Nanoha Multiverse. With just 5% of her power she was able to beat Magical Girl Hayate and with 6% she was able to beat Reinforce, the original Tome of the Night Sky. Shortly after she was able to one-shot the three materials, who were able to fight evenly with Nanoha, Fate and Hayate, being dark clones of them. This is consistent with her tanking the Triple Breaker, the combination of Nanoha's Fate's and Hayate's ultimate attacks. 

For reference, Nanoha, Fate and Hayate were stronger then Chrono's ice magic which could freeze so much water that it would take over 34 teratons of energy, which is enough energy to destroy a country. The Book of Dark, likely using Reinforce's power was vastly superior to the point that even a part of it, it's defense program required the usage of a TSAB Arc-en-ciel to destroy while the mages regular attacks could barely damage it. The Book of Darkness was also stated to be able to destroy the world and was said to be a more powerful Lost Logia to the Jewel Seeds whose powers were stated to have destroyed worlds in the past (Though this may be via spatial disturbance). 

However even this is not the true power of Unbreakable Dark. Material-S claimed that Unbreakable Dark had an infinite power, and though that is likely a hyperbole, it speaks to truly how powerful she is relative to the rest of the cast. It was also stated that she is able to destroy 2 or 3 planets in a single attack! Given the distance between planets, this means she is likely in the large planetary range at her maximum. 

In terms of speed, even Nanoha-verse drones inferior to any low-tier are able to move at mach 61 and S-tier mages can react to lasers that are encompass wide parts of the massive TSAB headquarters quickly, calced at Mach 1477. Fate Testarossa as a speedster by StrikerS was able to move so fast that another mage thought she was a teleporter meaning she would likely have to be relative such a speed. Given Unbreakable Dark' sheer level of power it's likely she scales to this level of speed.

Unbreakable Dark contains many of the same abilities of most powerful Nanoha fighters. She can fly and fire magic blasts. She has numerous layers of barriers, protecting against spacetime manipulation, dimension manipulation, magical effects, physical phonema, and environmental effects. Unbreakable Dark can grow her barriers to encompass an entire city. She has passive telepathy and scanners that give her advanced sight options (such as seeing the angles mathmatically pop up and seeing at range, as well as detecting potential threats). She has binding able to bind up even the Materials, etc.

Unbreakable Dark also has more unique abilities. she can manipulate darkness and from them can materialize wings and claws to use as additional weapons. She can also use the technique "Ancient Matrix" to impale her opponent on a blade coming from another dimension so they won't can't block it, and then cause it to explode inside them.

Most notable about Unbreakable Dark's powers is her control over spacetime. Her control of space is enough to cause a dimensional tremor, a disturbance in dimensions that can destroy planets or even entire "dimensional universes". She can teleport herself or others, even through dimensions. Her presence was warping and distorting spacetime summoning beings from alternate timelines and other times such as bringing Fate's abusive mother Presea to her time to disorient and weaken Fate's will. A Drama CD reveals this even allowed the anime-canon Nanoha cast to meet their equivalents from the As film canon despite said film being a film made a work of fiction in the Nanoha anime canon suggesting she was even bringing fictional characters to life. 

Unbreakable Dark can also summon dark versions of any entity she has encountered, with the same powers but opposite in personality such as Material-S being rational and cold, Material-L being psychotic and chaotic, and Material-D being arrogant and commanding in contrast to Nanoha's emotionality and naivety, Fate's nobility and protectiveness, and Hayate's humility and sweetness respectively. 

Unbreakable Dark can also resurrect others and revive infinitely so long as the Master Control Program of the Tome of the Night Sky, now known as Reinforce, exists. This is a form of low-godly regen that requires destruction of either Reinforce or Unbreakable's information to destroy. Also Unbreakable Dark possesses the Examia crystal maintained by the Eternal Ring program which allows her to regnerate the pieces of the Book of Darkness into pieces back into reality as her minions, which possibly gives her access to the other haxes of the book of darkness.

Unbreakable Dark has a few weaknesses. Like all Nanoha programs she is capable of entering a berserk mode if she is sufficiently threatened and loosing control of her powers and and as essentially technology, she is vulnerable to technopathy and being hacked into or overwritten (which is why she was sealed away in the first place). She also relies on the Examia Crystal, and damage to it will severely weaken her.

Name: Unbreakable Dark, U-D, Sovereign of the Purple Sky, Successor of the Purple Sky, The True Darkness of the Book of Darkness, Yuri Eberwein, Yami-chan

Origin: Magical Girl Lyrical Nanoha

Classifications: Control Program

Powers and abilities: Superhuman physical capacities, flight, magic blasts, barriers (city-scale) against dimensional, spacetime, magic, physical, and environmental factors, telepathy and enhanced senses, binding, spacetime manipulation, summoning (alternate versions of characters, dark versions of characters, inter-dimensional exploding sword), can create dimensional tremors, inter-dimensional teleportation and bfr, resurrection, regen (low-godly), darkness manipulation, can create wings and claws out of darkness, possibly the other abilities of the Book of Darkness (Mind Hax, Soul Hax, Possession, Absorbtion etc.)

Weaknesses: Techopathy, can go into berserk mode and lose control, relies on the Examia Crystal and Reinforce 

Destructive Capacity: Country Level+ when weakened, Large Planet Level at full power. Universal with Dimensional Tremor

Range: Likely Inter-Planetary. Universal with Dimensional Tremor, Multiversal with spacetime summoning

Speed: Likely Massively Hypersonic (Mach 1477+)

Durability: Country Level+ when weakened, likely Large Planet Level at full power. 

Stamina: Infinite

Standard Equipment: Examia Crystal and Eternal Ring Program

Intelligence: About average

So how would she do in other verses?

In the Marvel Universe, her stats at full power would be relatively strange, as most beings that are in the large planetary range are at least FTL. She would be most likely considered a low herald level being though the amount of technopathy in the Marvel-verse would not bode well for her. That said her ability to create alternate universe versions would be incredibly broken for the verse as there is often incredibly and insanely powerful versions of most characters (though it would be most likely NLF to say they would still serve her). While her speed would be slow for her tier able to matched by the faster street tiers, her ability to destroy a universe would likely mean she would be at least regarded as highly dangerous. Her weaker form would be able to fight evenly physically with mid to high meta threats like Namor or Torch though she would likely win against either of them due to her potent haxes. 

Hilariously enough in the MCU, she would have fairly similar stats to Thanos himself, as Thanos with the Infinity Gauntlet tore a moon apart at nearly 1% the speed of light, requiring massively hypersonic speeds (consistent with him reacting to Thor's lightning) and large planetary levels of power. While she would very likely not beat IG Thanos in a fight due to having high degrees of both stats, greater versatility and hax, and greater intelligence, she would have given him a bit of a fight depending on how he proceeded, and she could indeed have stopped him by summoning the 616 versions of the Avengers like Thor and Dr. Strange.

  

In the DC Universe, Unbreakable Dark in her weaker form would be approximately on par with High Tier Atlanteans like Arthur and Mera physically compared to their lightning timing and scaling to feats like sinking all of Atlantis. Unbreakable Dark would be perhaps a little bit stronger as that is more like the power of the actual S Tier Mages that Unbreakable Dark was considered vastly stronger then. She would also have a strong diversity of haxes and similar to Marvel, would be able to summon massively stronger versions of characters. Her stronger form would be very awkwardly placed, with essentially no character to compare too. Fittingly she would most closely actually compare to high end technology like the Gordanians ships being able to violetly disintegrate moons.

In the Teen Titans animated universe she would actually be relatively similar in power and speed to Trigon who destroyed the surface of the Earth at relativistic speed, requiring large planetary levels of power (consistent with being massively stronger then Teen Titans Starfire who was able to survive a planetary level explosion) and White Raven overpowered him and restoring the Earth. Teen Titans Trigon vs Unbreakable Dark alone would actually be a really interesting fight with U-D being unable to use her alternate versions ability since any version of Trigon would be an enemy towards her. While Trigon could win via sealing and or reality-warping, Trigon is more likely to estimate Unbreakable Dark and I would guess she would win via her more hax abilities. Her vs White Raven would also be a very interesting fight though I would bet on White Raven winning via empathetic manipulation calling out to Yuri's true desire to not fight anymore, similar to Material-D's victory over Unbreakable Dark or how Hayate stopped Reinforce initially.

  

In the Pretty Cure-verse, one of the two big modern magical girl series started in the same year as MGLN, Unbreakable Dark would be strong enough to contend with numerous pretty cure teams. In her weakened form, she would be roughly as strong as the Suite Pretty Cure team whose movie villain could destroy whole kingdoms. While she would be slightly slower, she resists literally all of their abilities and could return as many times as needed as well as simply bfr to another dimension. She could even defeat Noise this way, even though Noise comes back so long as sadness exists on Earth, dimensional bfr should incapacitate him. 

In her stronger state, she can threaten almost anyone in the verse with a dimensional tremor, and her power is enough to overwhelm the Hugtto, KiraKira, and GoPrincess Cures. There are more cures she could overwhelm in terms of raw power but is slower then (like Heartcatch!). All these groups have hax, but outside of maybe Dyspear, I think it's likely Unbreakable Dark's hax would be able to match. She would roughly be comparable to the Smile Cures in their Ultra state who defeated Emperor Pierrot after he grew massively larger then the Earth and who scale to lightning attacks. While she would defeat most of the Smile Cures, Smile Happy's literal Plot Hax to force a happy ending would probably allow Cure Happy to befriend Unbreakable Dark. She also gets hard countered by Moebius' technopathy

In the OTHER big modern Magical Girl series, which Magical Girl Lyrical Nanoha has actually crossed over with and Akiyuki Shinbo helped create both, Unbreakable Dark in a weakened state would fit well amoung the stronger entities in the time of Tart Magicka, being roughly comparable in stats to Isabeau. She's not as hax as Isabeau, though Isabeau would probably find it hard to permently put down Unbreakable Dark. Ultiamtely she would be roughly in the range of the holy magical girls and of Corbeau. Her ability to summon alternate versions of characters might be really strong however, depending on how strong versions exist of some beings.

In her stronger state, she would be a bit awkwardly placed, as the large planetary beings in Madoka like the Madoka Robots are much faster then Unbreakable Dark, though U-D is more hax then they are. In the end she'd be probably about as strong as they strongest non-god tier entities. 

Infamously, spacebattles suggested that Nanoha would beat Dark Schneider, (and Nanoha is technically a spin-off of an eroge) so how would she do in the Bastard!! verse. Well no suprise Dark Schneider currently and for a long time, has been able to solo MGLN. The weaker version of Unbreakable Dark could probably have a reasonably even fight with Pre-Reincarnation Dark Schneider or other extremely powerful Earth Mages. 

Full Power Unbreakable Dark would be stronger though slower then the Angels and Demon whom generally have planet-destroying capacities and speeds exceeding that of light, very often by thousands of times. They also would both mutually struggle to harm each other given Angels Eternal Atoms which Unbreakable Dark would have extreme difficulty doing anything too even with the powers of the Book of Darkness and Dispel Bounds which she simply is never going to get through. On the other hand they would also have difficulty hurting her, though I get the feeling any attack that can destroy eternal atoms like the seraphs have would work as they destroy their presence throughout the universe and also remove them from the sequence of causation. If she could teleport them, she could hypothetically BFR as it takes beings on the level of Fallen Uriel Augoeides and Dark Knight Lucifer Dark Schhneider to break through dimensional barriers. Problem with that is that she would have to get through the Dispel Bounds that prevents bfr. At best her dimensional tremors might be able to kill a high tier character from Bastard!! Overall she'd probably be about on par with the general angels and demons, both being only able to kill each other with high difficulty, far from the high tier angels and demons let alone Dark Schneider's position.