So this is just a list of fights that either didn't happen, happened so briefly they didn't really count, or happened off screen that I would have liked to see from my favorite series. Because I like to specify what I'm considering for my parameters I've seperated into 3 basic qualifiers.
1: How entertaining a spectacle would it be. This takes in a number of factors. Generally if the two characters are vastly uneven then it's not very entertaining to watch unless you really don't like the weaker character, even then for me that's not a big plus. But more then that, would the two characters fighting be interesting to watch. On some level this is just a question of how interesting the powers and intellects and personalites of the two characters are seperately but there is also a bit of a layer of would they interact in an interesting way.
2: The emotional/character potential of the fight. Do the characters have some kind of association that would make it interesting to watch them fight? Are they similar in a way or opposite in a way that means it would be interesting to see what they thought of each other? Stuff like that where it would be interesting on a character level to see what would happen if the two came into conflict.
3: The story potential of the fight. Is this a fight that simply doesn't make sense to have happened or is it something that could easily have happened? Would them fighting just cause problems with the story or would it actually have enhanced the overall story? There are some fights that would be fun to watch by themselves but would take so much time to set up and then absolutely mess up the narrative afterwards.
As a quite note, for game characters this is assuming you either get to take control of one of the characters or they fight in some kind of adaptation and not that there's some massive cutscene of the two fighting.
20:
Literally any Chaos Star Fight (Sailor Moon)
The reason this one is so low is it's the only one that has a negative story potential. These characters are all aspects of the same entity and the final boss of their own respective arcs so making them fight and not wrecking the story would be really difficult.
That said, despite Sailor Moon being my favorite series ever, one of the tropes I really like that isn't really in it are villains fights despite the fact that the Chaos Stars have some of the widest variety of abilities in SM and would be interesting to see interact a lot. Not a huge amount to say I just think seeing two of these fight would be really cool and one of the best SM fights.
19:
Tart vs Giant Wraith (Avatar of Calamity) (Puella Magi)
Tart is the Magical Girl form of Joan of Arc, the Heroine of Europe and the strongest Puella Magi-verse Magical Girl outside Kami Madoka and Akuma Homura (if she is considered a magical girl in her Akuma Form). The Giant Wraith is an avatar for Kriemhild Gretchen after a normal Moksha Wraith was infected by Homura's emotions and memories.
This fight would ALSO be really difficult to set up as they come from totally different times, but it would really cool seeing if the Magical Girl of Legend could take down this being that was fighting all of the Magical Girls of the Present Day. The two also both have really strong arsenal of abilities and I think it would be interesting to see what they would make of each other.
18:
Gemini Saga vs. Gemini Cain/Abel (Saint Seiya):
Gemini Saga is the Gemini Gold Saint of the Modern Era, holding two personalities that war within him, the Good Saga and the Evil Saga. Gemini Cain is the Gemini Gold Saint of the 18th century, who has a darker "twin brother" within him, Gemini Abel who emerges when his younger twin is "too weak "
This one would also be a bit hard to set up as the two come from entirely different times, though with the time travel and resurrection used in Saint Seiya it would be a bit less of a pain. While it would be a similarly intense figth I believe, I think it would be really cool for a character point.
Like the namesake sign of the Twins (Gemini), both Saga and Cain/Abel have split personalities between a good self and an evil self, even if the way it works is a bit different for both. They're both among the strongest Gold Saints and it would be interesting to see, perhaps if their evil selves are trying to kill each other while Good Saga and Abel are trying to protect the other.
Arthur Kirkland (England) vs Honda Kiku (Japan) (Axis Powers Hetalia)
Arthur Kirkland is the Embodiment of The United Kingdom while Honda Kiku is the Embodiment of the State of Japan.
So on the one hand this fight would probably lack a lot of the sheer spectacle since Hetalia fights tend to be fairly simplistic since the countries tend to act mostly like humans when fighting, though both Japan and England have supernatural abilities that could make it more interesting. It's in the other two degrees that this fight would excel.
For those who don't know, before the second world war 2, England and Japan had a fairly close alliance, that seems at first glance to make sense. The two countries are both fairly formal Island Nations that don't like to get close to the mainlands, often have rivaliries with the mainland nations, love tea, have important monarchies, are about the same size. However the disaserous effects of the 1919 Paris Peace Conference where England refused Japan's Racial Equality Clause. As Hetalia was initially set in World War 2 times, and the two countries were actually at war, it could have been great to see the two nations fight and this to be even brought up. Granted Hetalia is pretty light most of the time but I think it could have made for a very moving confrontation.
Ninetails is the 9-Tailed Demon Fox, the main antagonist of the Second Arc of Okami a crafy shapeshifter. Orochi is the 8-Headed Serpent Demon, the main antgaonist of the First Arc of Okami and Amaterasu's original rival.
This fight would be very easy to set up as the two were both on the Ark of Yamamoto together and Orochi only needed to eat one more maiden to recover his true power. He might think that Ninetails might work. Orochi probably has more power in the Ark of Yamamoto but Ninetails is smarter and has the dark celestial brush which is the dark equivalent to what Amaterasu used to defeat Orochi. I think it could be a really interesting fight and it would be interesting to see the two arrogant personalities clash.
15:
Unrestricted Wuya vs EOS Xiaolin Dragons
Wuya is the strongest of the Heylin, a villainous group. She is a witch from ancient times seeking world domination. The protectors of the world are the Xiaolin Dragons, 4 wuxia using martial artists controlling the elements.
This fight was actually suggested to me and was better then what I had thought up. Wuya had been the main villain of the series since the very beginning of the series, literally the first few minutes and her full power was enough that the strongest villain for most the series Chase Young didn't dare bring her back with.
You'd have some nice symbolism to play with since Raimundo went from least reliable of the Xiaolin Dragons to their leader, and the last time Unrestricted Wuya appeared was via Raimundo's betrayal, his lowest point. You could also draw parallels between Raimundo's attitude and Dashi's attitude. The story potential of this is somewhat low since this would by definition have to happen at the end of the series but it would be a pretty good fight most likely.
14:
Ruby Moon vs Yue (Cardcaptor Sakura)
Yue is the first Lunar Clow Guardian. Ruby Moon is the second Lunar Clow Guardian.
The two did briefly conflict but it was really quick. A full fight between these two would be really cool. They are two of my favorite CCS characters and they already have a clear relationship, specifically with Ruby Moon's teasing of Yue, pretending to try and pursue his boyfriend Touya and also telling him that she is the new improved model of him. Ruby Moon is a very expressive character with Yue is very stoic so they would compliment as opposites. The two also have a diverse arsenal of abilities and are both intelligent spellcasters. Both being the Lunar Card Guardian they have the full arsenal of Lunar Magic including things like Dream, Sleep, Erase, Darkness, Water, Wind, Mist, Shadow and so on.
It wouldn't have a huge potential to add to the story though it also would be easy really easy to set up as the two did briefly fight when Eriol was attempting to push Sakura into transforming Light and Dark.
13:
sans vs Flowey (Undertale)
sans is a comedic character from Undertale, a goofy skeleton with subtle characterization suggesting he suffers from a nihilistic lack of meaning. He serves as the final boss of the Genocide routes, despite being technically the weakest monster in the underground, using fourth wall awareness and strange special abilities to fight Genocide Frisk. Flowey is the primary antagonist of UT and in different forms the final boss of the other 2 routes. He is most known for controlling the broken power of DETERMINATION which allows for the abilities of SAVE and LOAD.
This is a fight that technically happened canonically, as Flowey mentions sans caused him more then his fair share of resets. What I like a lot about this fight is that it's basically the two hax fighters of the verse fighting. Like a lot of UT fights, the actual mechanics of the fight would be a reflection of the fight's character and symbolic intents, as Flowey can retry so long as he has DETERMINATION so sans would have to break Flowey's determination with numerous extremely fights as he tried to do against Genocide Frisk.
From what we hear that did seem to be what happened, and this would set up the Genocide Route as well, since it would support the player's DETERMINATION being greater then Flowey's which Flowey supports. Though you could say the actual fight mechanics would be a bit inelegant. Flowey's base doesn't have much interesting abilities.
12:
Vlad Plasmius vs Fright Knight (Danny Phantom)
Vlad Plasmius is the primary antagonist of Danny Phantom, an older half-ghost then the main character that wants to possess things that he can't. Fright Knight is the spirit of Halloween and a powerful ghost entity.
This fight would be really easy to set up and just setting it up would be entertaining. The two already seemed to form a secret alliance as of the Pariah Dark fight. It would make total sense for the two to engage in some attempt at taking control, only for a classic villainous backstab. Technically the two did fight briefly with FK seeming to be a bit more powerful but it's very likely Vlad has improved since then and it would be actually a good way to show it if they are about even. It would also be somewhat interesting tactically since Vlad would have to use his duplicates to avoid being hit by FK's sword. This has a lot of story potential in being set up, albeit I'm not sure how much character mileage you could really get from it.
Yomi vs Mukuro (Yu Yu Hakusho)
Yomi and Mukuro are two of the Three Demon Kings and the only 2 after the death of Raizen. Mukuro was a child sex slave and deliberately disfigured herself so she would be thrown out. She then worked herself up in power until she became one of the strongest demons in Demon World. She wishes to keep the status quo of Demon World, seperate from human world occassionally going up and stealing humans to eat. Yomi was a demon bandit following the demon fox Kurama until Kurama sent an assassin to kill him for his failure, ending up blinding him. Knowing he would need to improve or inevitably die, Yomi improved in power until he became one of the strongest demons in Demon World. He wishes to unite human world and demon world under his control.
I honestly think the reason this fight never happened is it was so hyped up that any fight between them would have felt like a disappointment :P Outside of Raizen and his buddies, these two are the undisputed strongest characters in the entire verse and are canonically incredibly close to each other in power to the point that armies of S Class Demons are almost meaningless on one side or the other, and Yomi could not use even 1/8th of his power against Yusuke and Hiei or Mukuro would kill him. The two canonically hate each other, as well, one being a random ball of emotion and chaos, the old being a cold planner.
10:
The Domain vs Time Master (Freedom Force)
The Domain are a Multiverse-Spanning Alien Empire who are the source of the superpowers in the game as they wanted to see Earth tear itself apart with superbeings. Time Master is the multiversal lord of time who was seeked to stop al time to live forever.
This fight was supposedly going on off screen, with the Domain, the Multiverse Spanning villainous alien civilization somehow holding the Cosmic entity Time Master. I would have loved to see how that was possible, and as a bonus we would actually get to see more of what the Domain is made off. In the game they don't come across as the intimidating as they're supposed to. Mentor does a great job of hyping them but we see them only briefly and they weren't honestly more impressive.
It would have been really great if there was perhaps a flashback where we play as Mentor as he led a group of Domain Warriors before their corruption using the Domain's canonical trans-dimensional trans-time technology to launch an assault to weaken and subdue Time Master. Granted Mentor doesn't know about Time Master at the start so you'd have to explain that but overall it would be really cool seeing the Domain being legitimately impressive, seeing the extent of their multiversal technology, and also hyping up Time Master.
9:
Ares is the main antagonist of God of War 1, the original God of War. Athena is the Goddess of Wisdom and Warfare and acts as Kratos' mentor in God of War 1 before gradually revealing that she is a manipulator who was acting to protect Olympus and later towards her own mysterious aims.
This is a fight that would have happened in canon if not for Zeus' law holding that the Olympians could not engage in each other in combat. Ares was going to destroy Athens, Athena's city, and Athena had to enlist Kratos because she could not wage war with Ares directly.
Without Zeus' law Athena could have engaged Ares himself, and had Kratos retrieve Pandora's Box basically as a backup plan, while pretending to Kratos she only plans to hold Ares until Kratos gets the box. This would clear up the plot hole in the first game of why Giant Ares didn't destroy Athens in the more then 3 days it took Kratos to retrieve Pandora's Box. Ares and Athena are both among the six Gods honored by the Fates so it's likely they are of similar power and it would give Athena a chance to fight that never happened in the game. You could have I think some interesting interactions between the God and Goddess of War, hype up Ares by having him slowly win their direct confrontation while also showcasing Athena as a manipulator which would be her characterization in later games.
8:
Lord Dominator vs Major Threat (Wander over Yonder)
Lord Dominator is the primary villain of Wander over Yonder, a Galaxy Destroyer of absurb power primarily lava oriented. Major Threat is the villainous idol of the first big bad Lord Hater, who primarily uses telekinetic powers.
So Word of God is that Major Threat "probably would not" defeat Lord Dominator suggesting he is somewhat relative but below Lord Dominator. Major Threat was actually there at the final battle for the last planet in the galaxy. It would have been really cool for a lot of reasons if Major Threat had pulled out all the stops and tried to telekinetically hold Dominator and her lava back like Tien vs Cell. The really interesting part would be the effect on Hater. This would be symbolically Hater directly seeing that the villainous archetype embodied by Major Threat while it could struggle with Dominator wouldn't be able to win, especially if he also notes that Major Threat since becoming good is a lot stronger then he was back when Hater watched him as a villain (something as simple as noting "I've never seen him do something like this...". This would be a really good foreshadow of Hater's overpowering of Dominator.
It's a bit simple sure, but it would be a brief spectacle and it would allow for both an interesting character dynamic and also add an extra symbolism to the final battle.
7:
Dark Samus is the revived Prime Metroid by the power of Phazon, having absorbed her Phazon Suit. SA-X comes from when the X Parasite infected her Power Suit mimicking her.
Already you can probably see the thematic of these two being both being essentially Evil counterparts to Samus, one being Metroid one being X Parasite. The only the real caveat I see with the fight is that it's almost canonically a stomp for Dark Samus. Not only does she have way better abilities, fought a much stronger Samus, buit Metroids are the hunters of the X Parasite. It's basically thematically a stomp, you'd have to justify it by saying that Dark Samus' regeneration after Phaaze's destruction severely weakened her which wouldn't be hard to justify as the destruction of Phaaze was supposed to have destroyed all phazon in the universe.
It would also be a dark reflection of Metroid Fusion's plot as Fusion involves Samus herself becoming ironically part Metroid to hunt the X-menace. Dark Samus is the Metroid Prime and if there was some kind of manga alternate timeline of Metroid Fusion, I think it would be really cool if Dark Samus returns during the events of Fusion weakened. Dark Samus pretends to form a temporary alliance with Samus to fend off SA-X (pretending perhaps to view her more favorably as a fellow Metroid) only to be planning to betray her and take the power from SA-X's defeat. It would also give SA-X much more threat then it had in the game to see it fighting off both Samus and Dark Samus.
6:
Zatanna vs Raven (DC Comics)
These two DC dark aesthetic DC Mages are known for not liking each other very much dating back to their first interaction when Raven when to the Justice League seeking help against the demon Trigon and Zatanna warned the JLA she sensed a dark aura within Raven (this being because Trigon was Raven's father). Beyond that though the two simpily don't get along well. Zatanna is social, playful, open, non-chalant, and so on while Raven is more guarded, anti-social, broody and private. The two simply don't get along very well.
The two are also relatively, as both have universal levels of power sealed with them by their fathers. In Zatanna's case, her father Zatara sealed with her the 4 primal elements in her 4 noble qualities while Raven had demonic power of Trigon and later the souls of Azarath sealed within her. The two both also cast spells by speaking unlike other mages in the DCU. It would be I think a relatively interesting and even fight.
They even had the perfect opportunity to do so during JLA/Titans: The Technis Imperative where for plot reasons the two groups had to essentially pretend to fight.
5:
Rosa is the mother of Bayonetta who was killed by Loptr and was one of the most powerufl of the Umbran Witches, so skilled as to impress Bayonetta. Balder is Bayonetta's father who was the villain of the original game,
This fight would really interesting on all 3 accounts, I believe. After Bayonetta and Balder are set back to the past, Balder attempts to seal Loptr within his soul similar to how he would at the end of the game and turn evil. Rosa, realizing there's something wrong with her beloved confronts him leading to a evenly matched confrontation of the powers of dark and light. Balder wins via Loptr's power within him and Rosa's dying words to her beloved asking him to return to his senses and that he needs to protect Cereza breaks him out of his control by Lotpr, which also frees Lotpr again.
This would be a really interesting character fight I think! It would be fairly easy to set up and would foreshadow the ending of the game where Balder again seals Loptr within himself. It would especially be cool if they are both using climax attacks to fight with demons and angels.
4:
Grimnir vs Lok (Magicka)
Grimnir is the main antagonist of Magicka 1, who through hard work and experience sought to unite the world under his rule to end the senseless chaos and violence of Midgard. Lok is the Chosen Child, the main antagonist of Magicka 2 born with the natural magical power formed of the senseless chaos and violence of the Wizard Wars who sought to unite the civilized races against the monsterous races of goblins, orcs and so forth.
This would be one of the most evenly matched fights in the Magicka word, a match between Grimnir's magicka, experience and long term experimentation vs Lok's sheer natural magical power and the extensive list of elements she has access too. The two would also have interesting character perspectives going against each other. Grimnir would see Lok as almost the embodiment of the senseless chaos that he has devoted himself to fighting as Lok was formed from the raw magic of the Wizard Wars. Meanwhile Lok seeing herself as the champion of civilization would likely view Grimnir as some kind of shifty strange wizard at the fringes of civilization, similar to how the wizards saw Grimnir in the prologue of Magicka 1 and why they imprisoned him at World's End.
The fight seems like it wouldn't be easy to set up since Grimnir died but death in Magicka is.....kinda pointless. Grimnir could very well have come back and fight against Lok, which could either have hyped Lok as a villain or acted as a surprise boss of Magicka 2 if Grimnir had like the Player Wizards learned the Disruptor and stolen Lok's sheer magical power.
3:
Zagato vs Lantis (Magic Knight Rayearth)
Zagato is the primary villain of the first half of Magic Knight Rayearth, who fell in love with the pillar of Cephiro, Emeraude and stole her away so she would no longer suffer even if it means destroying Cephiro. Lantis is the love interest of Hikaru, the main character of the series, a powerful swordsman and magic-user and one of the strongest fighters of Cephiro. He is also Zagato's twin brother.
This fight practically rights itself on all levels. It would have been completely possible for Lantis to hear what Zagato was doing to Cephiro and return to stop him. There's no seen interaction between the two brothers since Lantis only appears in the second half after Zagato is dead. The two would be likely be completely even being both incredibly skilled at both swordsmanship and magic. Zagato may have a rune god, but Lantis power is actually shown to rival a Rune God.
There could also be an extremely powerful emotional moment based on one of the creator's statements. It is noted that Lantis would have been a perfect candidate to be a Pillar of Cephiro as his will to destroy the Pillar System was so strong (as the Pillar is determined by the greatest of wills). Zagato could be angry that Lantis seems to be protecting the pillar system he hates so strongly regardless of the suffering it brings to the pillar and ask why he didn't take the burden on himself instead of abandoning Cephiro. There's just so much potential for this fight.
2:
Pegasus vs Bakura (Yu-Gi-Oh!)
Pegasus is the primary villain of the Duelist Kingdom Arc of Yu-Gi-Oh and the inventor of duel monsters. Yami Bakura is the primary villain of the final arc and arguably the entire series, the fusion of the souls of the Bandit King Bakura and Zorc Necroshades the lord of darkness.
Technically Bakura killed Pegasus in canon, taking his millennium eye however it would have been really great if the two had actually dueled. After seeing Yugi's strategy, Bakura could hypothetically forcefully switch to Ryou Bakura or possess him again to avoid Pegasus' Millenium Eye Reading. Their stratgies line up interestingly. Bakura probably couldn't rely on Destiny Board since Pegasus uses Magic Neutralizing Field but Bakura has a very plausible way around Toons since Toons CAN attack each other and Dark Necrofear could possess their souls, forcing them to fight.
This fight would serve to hype up Bakura more since in the original, Bakura never wins a duel agains a really strong duelist, though he does well against both Yugis and against Kaiba on different occassions. Showing him beating the creator of duel monsters would be good hyping as well as a good duel. There would also be more symbolism to it and foreshadowing as Bakura, acting as Zorc's emissary would probably allude to Pegasus that this whole time he was just the pawn in a greater game (foreshadowing the game at the end of the series) and that he was playing with forces far beyond his comprehension. Not only would that be a chilling moment, it would foreshadow Zorc, and would also be a fitting end to Pegasus character since Pegasus was characterized as constantly trying to take what was not his hence why his boss monster was Sacrifice (Relinquished) which takes the other player's monsters.
1:
Cure Happy vs Noise (Pretty Cure)
Noise is the primary antagonist of Suite Pretty Cure, the 8th Season of Pretty Cure. He is the embodiment of sadness and hates the painful song of happiness he views as hateful noise. He wishes to all sound including the "heartbeat of life", and while this will kill him he will be happy to finally reach the beautiful oblivion of silence. Cure Happy is the main protagonist of the 9th season of Pretty, Smile Pretty Cure. She is a seemingly incredibly optimistic cheerful hyperactive girl with an obssessive love of fairy tales. However her true self was actually sad and lonely and timid which she occassionally reverts too. As a little girl she loved fairy tales because of the power of "happy endings" and determined that she would try live every moment with happiness. She is "Cure Happy" not because she is the naturally most happy Pretty Cure but because happiness meant everything to her.
This fight is just too perfect and it's a traversty the two never actually encountered each other or fought. They are almost perfectly framed to conflict. Cure Happy's complete rejection of sadness is the embodiment of the pain and rejection the world gave Noise. Noise and his eternally regenerating nature is the embodiment of the sadness that Cure Happy can not banish from her heart. The two are perfectly framed to conflict.
Also while the Suite Pretty Cure together were able to stop Noise, Cure Happy is I believe the only Pretty Cure that would be able to defeat Noise by herself due to her ability to cause a happy ending to occur by the sheer power of her belief in happy endings. Noise was initially defeated by the Suite Team accepting him, accepting that being sad is a part of life. I believe Cure Happy's power of happy endings would allow her to befriend Noise, causing the two to finally be at peace with each other's existence, understanding that sadness would always come back at some time, but that this is not the end of the story, that a happy ending would come later and that sadness is not something to be feared; the strange mixture of emotions that life is comprised of is part of why it's worth living.
I could go on and on about this one, this fight would just be too perfect.
