One of the reasons why we love The Bridge so much is that Tarbtano and his team were able to bring two franchises together and combine them in an excellent way. Both sides get to show why they are awesome while not overshadowing the other and Kaiju characters demonstrate a level of depth we never would have expected. Of course, we have our fair share of haters who believe that the Kaiju should remain mindless beasts and utterly curb-stomp the Equestrians, but forget them.

Let us discuss crossovers (can be for any franchise) that are excellent or otherwise interesting.

Equestria Girls: Friendship Souls (My Little Pony: Equestria Girls / Bleach)
Premise: Shortly after the events of Friendship Games, Sunset Shimmer, Sci-Twi, and the Humane Five discover the existence of the Hollows threatening their world and the Soul Reapers who fight them, and discover secrets about their own pasts.
My Notes: What's really cool about this is how nearly every Bleach character has been replaced by a FIM character in a way that makes sense.

You Can Lead a Horse to Water... (My Little Pony: Friendship is Magic / The Familiar of Zero)
Premise: Louise summons Trixie as her Familiar. However, before Louise can kiss her to inscribe the runes, Trixie escapes! While Louise struggles to figure out what to do, Trixie wanders the country using an illusion to appear human while trying desperately to figure out a way home.
My Notes: There are so many The Familiar of Zero fics where Louise summons someone other than Saito, but this one is so bold to put a new spin on that usual formula.

Kick about! Los Lobos! (My Little Pony: Friendship is Magic / Bleach)
Premise: After Coyote Starrk and Lilynette Gingerback were killed in the Fake Karakura Town, they unexpectedly wake up in Equestria as ponies. Derpy and her family takes them in, and they attempt to adjust to their new lives.
My Notes: Besides the fact that the cover image is absolutely hilarious, this fic is really fun, and Starrk and Lilynette both get to show how awesome they are.

Cry For An Angel (The Familiar of Zero / Heaven's Lost Property)
Premise: Louise summons Ikaros as her Familiar. However, the usual Familiar of Zero plot is soon changed when Minos orders his Angeloids to investigate the worlds and retrieve his lost property.
My Notes: Like I said, I like new spins on the usual "Louise summons someone other than Saito" stories. Also, the friendship that develops between Louise, Ikaros, and Tabitha is adorable.

Celestia Takes A Vacation (My Little Pony: Friendship is Magic / The Familiar of Zero)
Premise: Set about 300 years into the future of FIM, Twilight and Luna convince Celestia to take time off and go on a journey for about 100 years, assuring her that they can take care of Equestria. She agrees, but is shortly afterwards summoned by Louise as a Familiar. Amused by all of this, Celestia decides to spend her vacation teaching Louise how to control her magic.
My Notes: Written by the same person who did Cry For An Angel. This fic is very fun and Celestia basically becomes a second mother to Louise. Warning for those of you who don't like that sort of thing: there are girl/girl relationships here.

Fates of Ice and Fire (Fate/Zero / A Song of Ice and Fire)
Premise: During the Fourth Holy Grail War, seven totally different Servants are summoned. Ser Jaime "The Kingslayer" Lannister is Saber, King Robert Baratheon is Rider, Melisandre is Caster, Prince Oberyn Martell is Lancer, Ser Gregor "The Mountain" Clegane is Berserker, Arya Stark is Assassin, and King Joffery Baratheon is Archer. All of them brought their own history and regrets. May the tragedy of blood and steel begin.
My Notes: If one knows anything about these characters, then they would see that their roles and Noble Phantasms make sense. This author also has a good understanding of the Fate series, in that Noble Phantasms come from the Servants' legends as well as what they had actually done.

The God of Destruction Comes To Remnant (Godzilla / RWBY)
Premise: The humans try to destroy Godzilla with an experimental weapon, but it instead transports him to Remnant in the body of a Faunus. A lot of asskicking ensues.
My Notes: This Godzilla is Godzilla Senior, but his world seems to be a blend of the various film series, as he mentions raising both Minilla and Godzilla Junior, and mentions events from the Showa, Heisei, and Millennium movies. He arrives in Remnant sometime before RWBY Vol 1. An awesome surprise is the reveal that Rexy and Blue from Jurassic World and the now grown up protagonists from The Land Before Time have also been sent to Remnant in the form of Faunus. Later, Mothra, her son Leo, Minilla, and Godzilla Junior arrive in Remnant in the form of Faunus.

God Slaying Blade Works (Fate/Stay Night / Campione!)
Premise: At the end of Fate/Stay Night Heavens Feel, Shirou is about to destroy the Holy Grail and kill Angra Mainyu, the God of Evil, at the cost of his life. Before he can, a warp transports Shirou, Illya, and Angra Mainyu to the Campione! universe. Shirou kills him there, and since he just killed a god, he becomes a Campione, an immortal with the powers of slain gods. Shirou learns to accept this, and he and Illya build new lives and form friendships, alliances, and enemies while trying to find a way home. Meanwhile in the Fate/Stay Night universe, Shirou's girlfriend Sakura Matou and his friends Rin Tohsaka and Rider attempt to move on, but when they figure out what happened to him, they decide to try to get him back.
My Notes: This fic has its fair share of haters, who similar to the haters of The Bridge, are offended by the very notion that the Campione! characters could even stand a chance against Shirou, and cannot stand Godou Kusanagi. I say just relax and enjoy it. One funny running gag is the Campione! characters and Shirou and Illya's wildly inaccurate assumptions about each other. Shirou vs Mordred The Black Knight is one of the most badass scenes. This story doesn't get updated very often, but when it does, the chapters are incredibly long.

I didn't like Kick about! Los Lobos. It was interesting at first, but it got tiring to read later on. Its written well, but I just didn't like how things were going.

The Dresden Fillies Trilogy (The Dresden Files/My Little Pony: Friendship is Magic)

Currently has two completed stories: Strange Friends and False Masks. The third and final one, Great Power, is currently underway.

Premise for Strange Friends: after opening a portal at complete random to flee from some monsters, Chicago's resident wizard-for-hire Harry Dresden finds himself in Equestria. He very shortly meets the mane six and hilarity ensues. But when Spike gets kidnapped, Harry lends the ponies his investigative expertise to help find him.

My Notes: This fic hits all the right crossover notes, and I personally think it stands on an equal level with The Bridge. The concepts and characters from both series are excellently showcased, and the story can serve as an introduction to either series for new readers. One of the biggest high points is Harry's first-person narration segments. In the actual books, Harry narrates in the first person with a very distinctive, often snarky style. The author nails this style PERFECTLY, to the point that it may as well have been written by Jim Butcher himself. The tone is darker than typical FiM, but the overall cheer isn't lost and there's plenty of comedy. Highly recommended.

Deus Ex: Equine Revolution (My Little Pony: Friendship is Magic/Deus Ex: Human Revolution)

Premise: Mortally wounded after an attack on the Sparkle Industries laboratories by unknown forces, Bon Bon is outfitted with a large amount of cybernetic augmentations in order to save her life. After recovering, she sets off on a mission to discover who was responsible for the attack.

My notes: For those familiar with the game, that premise might sound identical to that of Human Revolution. It is, but the key is in the details. For one, the continuity is firmly set in the FiM universe, with everything up to the end of Season 3 being explicitly canon. The story itself is set 20 years after Luna's return, in a world that has seen war, overpopulation, and the rise of cybernetic augmentation. Although characters and events can often be matched up to roles from HR, it's not a direct one-to-one retelling, to the point that it'll keep you guessing even if you've played the game before. It does a great job of capturing the spirit of what Equestria might be like if it traveled down that sort of technological path.

One of the few rules I have on checking out fanfiction is that I should have at least a passing familiarity with all source materials, just so I don't get lost trying to keep up with who is who. Sadly, every story above involves at least one franchise I know very little about. I may check out the RWBY crossover, but that's about it....

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In that case, you may want to check out The Dresden Fillies. Harry is the only Dresden Files character that appears in the first story, so it'll let you get your feet wet.

Whelp, time to throw my hat in the pile I guess.

This first suggestion is kinda cheating since it's an author more than a single story, but he specializes in crossovers so I guess it counts.

Tatsurou, Author of the Adopted Displaced Series.
For the most part this guy's stories follow a simple formula: Pony (or other species) gets sent through time and space to another fictional world as a baby, is adopted by some of the characters in the world they arrive in, and then proceed to utterly break that world to their whim as they grow up, learning and adapting to the powers/skills present in their new home. Eventually they all return to Equestria stronger, happier, and overall way more badass than they are in original canon (usually showing off such by beating the st out of Tirek, the sorry sod.) The stories are for the most part lighthearted and not too in depth, but they are updated very rapidly, with 2 or 3 chapters of between 1-2 thousand words every week. If you want serious and realistic examinations of how a world would react to ponies, you'll probably be disappointed, but if you go in expecting mildly random and cute fun, then there's plenty to enjoy.

Friendship is Scaleless (MLP/Dark Souls Crossover)
This story takes the idea of crossing over two worlds and does it near perfectly, on the one hand showing off the very distinct differences and not so rare similarities between the two realms, while also melding elements from both together to show why these two worlds are interacting to begin with. As a warning, the story is a faithful rendition of Dark Souls, and thus is appropriately DARK. Do NOT go into this expecting simple and clean action. Bad things happen time and time again and hope is hard to find, but if you persevere, the light will guide your way. Highly recommended for anyone who is a fan of From Soft's magnificently bleak world, even if you aren't too into pony.

The Last Spartan (Halo/Mass Effect Crossover)
Supposedly one of the first, or at least certainly one of the biggest, crossovers of the two dominant sci-fi/space opera game series out there, this story is well deserving of its fame. On the surface it seems simple, just replacing Shepard with the Master Chief, but this is one of the most developed and clever examples of world melding that I have ever seen. The Covenant races have integrated with the ME world in ways that make perfect sense for their cultures (Elites are in competition with the Turians as dominant military, Jackals are cut-throat economic powerhouses, etc.), while the technology of both sides is compared and contrasted fairly. While at first some things seem to favor ME, later chapters show why things are in their current state and hint at changes to come. If you want to see Master Chief blowing up Geth or taking on biotics, that's certainly in there, but there's plenty more to see alongside it that makes it well worth the read.

The Mission Stays the Same (Mass Effect/Warhammer 40k Crossover)
This one is a tad more straight forward in the method of its crossover premise, simply dropping an Eldar and a high ranked Guardsman from 40k into the Mass Effect sandbox and seeing what happens, but it's no less effective for it. The fic takes great pains to show the very large gulf between the relatively friendly and open cooperation between races of ME and the inherent xenophobia both 40ker's show from their own personal experiences. Neither one becomes buddy buddy with Shep and the gang quickly or easily, but over time both are allowed to grow and change to fit this new world they live in. The 40ker's may be just a tad OP in comparison with the status of ME characters and gear, but the threats they face are still dangerous and menacing enough that tension is not lost because of it. Worth a look for a fan of either universe.

The Havoc Side of the Force (Harry Potter/Star Wars Crossover)
It was inevitable that a Harry Potter story would end up on here wasn't it? It's only like the biggest fanfiction group on the internet, so of course it would have a crossover with everything at some point. That said, this one stands out for being a relatively serious take on the idea of a Post-Voldemort Harry (gone full Marauder level trolling badass) ending up in a different universe with no resources, no idea of where he is, and no way in hell of ever getting back home. Harry as a character carries this story, his endless wit and snark in the face of the dangerous unknown providing the lift he (and we) need to keep going. Harry, being Harry, severely screws with the Stations of the Canon of the Prequel Trilogy just by being there, but the story also uses plenty of old EU material and new EU material to spice things up a lot. And in case all of this hasn't sold you already, Harry ends up getting HK as a companion. Yes, that HK. Take a read if you want to be entertained meatbags.

5844175 Funny, that passing familiarity rule is what got me into MLP in the first place. See, I found this Godzilla crossover that looked really good and was interesting, but for some damn reason it involved the kaiju being sent to pony land. I was like, "Okay, I need to know how in the hell this pony place could ever be a good fit for a Godzilla story, and trying to read this without knowing who is who and what is what is driving me bonkers." So, I looked up the first episode online, and suddenly I was hooked...
YOU HEAR THAT TARB! ME BEING A BRONY IS TOTALLY YOUR FAULT! AND I AM ETERNALLY GRATEFUL FOR IT!

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... for me, it was bouncing into MLP from Ranma by way of the Infinite Loops. MLP was one of the few franchises I was introduced to by looking into other loops that I decided was worth spending the time to get to know.

If you know the loops and look under a certain spoiler bar, you can guess why one of the above crossovers may well get a try from me....

A RWBY Zanpakuto (Bleach / RWBY)
Premise: To rescue Rukia from Soul Society, Ichigo had to regain his Shinigami powers. But instead of gaining Zangetsu in his inner world, he gains four Zanpakuto: Ruby, Weiss, Blake, and Yang.
My Notes: This fic used to be on fanfiction.net, but the author inexplicably deleted it and has completely ignored my messages asking why. I recently found this Russian website that has it (the fic is still in English), and one of the author's friends assured me that it is complete (the final chapter is kind of open ended, but makes sense as an ending). This fic is set in the Bleach universe, but with certain characters blended with RWBY ones in ways that make sense. For example, Nemu Kurotsuchi has Penny's looks and abilities. The characters also become much smarter and pragmatic than in canon.
Note: Sadly, the story seems to have completely disappeared from the Internet. Check out this blog for a more thorough summary.

The Bringer of Balance (RWBY / Godzilla)
Premise: It is the RWBY Vol 3 finale. Cinder Fall has the Fall Maiden's power and the Grimm Dragon and believes she has won. However, her actions have upset the balance, so Godzilla, King of the Grimm, awakens to set things right.
My Notes: This is heavily inspired by the 2014 Godzilla movie, as Godzilla is described as an alpha predator who balances nature. The fic ends on a sequel hook and the author has promised to eventually write a sequel.

Opening Dangerous Gates (Fairy Tail / Bleach)
Premise: Lucy acquires a black key that summons a random Shinigami when used and a white key that summons a random Arrancar when used. She attempts to master them while Fairy Tail staves off attacks from the demons of Zeref.
My Notes: The Bleach characters are several orders of magnitude more powerful than the Fairy Tail characters, but they are Showy Invincible Heroes and every time they are summoned, it's a real treat. Sadly, due to the author graduating college and becoming a full time nurse, the fic is on indefinite hiatus (she's promised to eventually get back to it, but tell that to the disgruntled fans), but enjoy what's there.

A Certain Duelist's Dream (Yu-Gi-Oh! / A Certain Magical Index)
Premise: Motor-mouth, a character from the fic Crisis on Two PokéWorlds!, gets challenged to a duel by a strange magician. However, every time Motor-mouth summons a monster, a character from A Certain Magical Index appears wearing the monster's clothes instead (like that episode of Yu-Gi-Oh! where Yami Bakura trapped Yugi and his friends inside their favorite cards).
My Notes: This fic was very fun, and though Motor-mouth and the A Certain Magical Index characters are incredibly weirded out by this, they become friends and help him win. It's also very creative how the author was able to choose monster cards that fit the characters very well. It has a sequel called A Certain Duelist's Dream 2: The Nightmare of GREMLIN, where Motor-mouth duels again and the same thing happens, with the twist that when his opponent summons a monster, a member of the villainous organization GREMLIN appears in the monster's clothes.

Crossovers to me are probably my favorite form of fictional medium, because it not only allows the blending of two universes together, but allows the ideas of mixing of ideas and characters, allowing them to bounce off each other to create something new. And, it's no secret that I have a lot of crossovers that I love:

Kingdom Hearts (Disney/Final Fantasy)
Yes, this is an "official" crossover series, it's probably the most influential when it comes to crossover, especially to my life. When I was a kid, I would freak out when two mediums would meet, thinking it was a kind of "forbidden rule" of stories. But low and behold, two of the GREATEST forms of entertainment, Final Fantasy and Disney, created something that not only combined the best of both worlds, but created a game series that was new, original, and was both fun, adventurous, sometimes nightmare inducing, and even a tearjerking story with a cast of characters we've grown to love. I mean, who doesn't love seeing Donald, Goofy, and the lovable dork Sora visiting our favorite Disney worlds, and beating the crap out of the Disney Villians we love to hate? And, I'll admit that the story has gotten a bit convoluted as of today, but it's a still fun series to play with characters we've come to love.

Shinji and the Doctor (Evangelion/Doctor Who)
Evangelion is probably one of my favorite anime, not because just because of the action, but of how the characters are so "real" compared to other fictional characters, with their own faults, highs, and especially lows. That being said, it's a series that I kind of have a love/hate relationship, especially with the movie "End of Evangelion", and the fate of all the characters at the end. Thus, one of my favorite aspects of the Evangelion fandom is the fictions that try to help characters, like Shinji, Asuka, Misato, and Rei have a fighting chance, and one crossover fic doesn't do it better, than "Shinji and the Doctor"! One miserable, rainy day, fourteen-year-old Shinji Ikari meets a very odd man who calls himself the Doctor (specifically, the Tenth Doctor) on a train. What follows is not only the mysteries of Evangelion being investigated by a rather UNIQUE individual, but also giving Shinji what he needed since the beginning of this life: A Mentor, who will not only help Shinji learn to overcome his faults, but may be the only person who can save this world from the horrors of Third Impact. What's great about this fic is not only the selection of characters, but how everyone plays off the Doctor, as the writing for this series is SPOT-ON with both Evangelion, and the sci-fi adventures of Doctor Who. I'm especially glad that the 10th Doctor was chosen, cause aside from the 11th, 5th, and maybe the 4th, I think the 10th is the most likely to be interested in Shinji's issues as well as the fate of humanity in this world. It's both funny, adventurous, and especially heart-warming.

Clash of Civilizations (Mass Effect/Halo)
What I love especially about science fiction is the idea of First Contact, where two new civilizations meet with new ideas and culture to explore, and what results come from the two meeting. Star Trek especially does this well, but this fic, in the Halo Universe after the war with the Covenant, humanity and the Sangheili discover that there's more out in the Galaxy, the Alliance from Mass Effect, consisting of the Asari, the Turians, and the Salarians. While many of our favorite characters from the Mass Effect universe reappear, such as Liara, Tali, Mordin, and even Saren, the circumstances of their character are bit different from canon, as this is the first time humanity has initiated first contact with them. And while this fic has plenty of action to keep you excited, a lot of the tense moments from this fic come from the attempts at first contact, as meeting another culture is not as easy as it looks, for the wrong move can mean the difference between peace....or war. And not only that, but the meeting between humanity and the Asari will awaken secrets between the two that were hidden long ago....

NGE: The Pokemon Raising Project (Evangelion/Pokemon) and Pokemon: JNPR Version (RWBY/Pokemon)
Pokemon is probably the only series that I still play through since it's conception, and it's not going to stop anytime soon. Thus, to me it's probably one of my favorite types of crossovers to see which pokemon would best suit the personalities of any fandom, such as characters like Shinji, Asuka, Rei, Jaune, Nora, Ren, and Pyrrha. Both these fics, by the same author no less, do this feature very well, as it not only blends both the original pokemon universe, but also mixes the original mythos of Evangelion and RWBY as well. So if you're a pokemon fan wanting to see characters you know and love try to catch them all, this fics are for you.

And these are only an inkling of the crossover fics that I love. There's plenty more, but I'm pretty sure that I'd take up the entire page if I talked about all of them.

I might as well include my own crossover. If it impressed Tarbtano enough that he shilled it in a blog, I must be doing something right.

The Lost Hero (My Little Pony: Friendship is Magic / Superman)
Premise: Superman is exiled to Equestria and turns into a pony. He befriends and goes on an adventure with Daring Do, Trixie, and Maud Pie.
My Notes: Tarbtano said he liked how despite the obvious power difference, I don't trivialize the ponies and I make sure they contribute. I also used a distilled version of Superman and also included several obscure comic characters in his backstory.

Kinda expected more responses, but oh well.

Crossed Paths (My Little Pony: Friendship is Magic / Samurai Jack / Indiana Jones)
Premise: The Mane Six, Samurai Jack, and Indiana Jones all find themselves in a strange world that seems to embody the worst aspects of their respective worlds and hold copies of their enemies. They must work together to figure out what is going on and how to escape.
My Notes: Sadly, the author has retired from this site, but this story is very heartfelt and tearjerking at times. It has a sequel called Desperate Times, where a year and a half after the events of Crossed Paths, the Mane Six must team up with Lara Croft from Tomb Raider and Sam Stone from the game Serious Sam, who have both been pulled into Equestria, to save the land from an invasion by the Burning Legion from World of Warcraft. That fic has been cancelled however.
Update: The author has for some reason deleted all their fics, but Crossed Paths can be found here.

Better Living Through Science and Ponies (My Little Pony: Friendship is Magic / Portal)
Premise: Shortly after Chell finally escapes the lab in the final scenes of Portal 2, a freak accident transports Chell, the facility, and GLaDOS to Equestria, where Chell becomes a pony. Chell embraces her new world, then must defend it when GLaDOS goes back to her old tricks and abducts several ponies to test.
My Notes: Chell's friendship with Ditsy Doo and Dinky is one of the most precious things.

What the Cat Dragged In (Marvel Cinematic Universe / Miraculous: Tales of Ladybug & Cat Noir)
Premise: About a year after the events of The Avengers (2012), SHIELD notices strange events going on in Paris, so Nick Fury sends Black Widow and Hawkeye to investigate. They are joined by Tony Stark who went to Paris on a business trip. They find out Paris has its own superheroes, Ladybug and Cat Noir, and some of the most bizarre supervillains they have ever seen.
My Notes: I feel this author writes it so well it could actually be plausible that Miraculous could exist in the Marvel Cinematic Universe.

Suzumiya Haruhi no Index (A Certain Magical Index / Haruhi Suzumiya)
Premise: The sinister Aleister Crowley learns of Haruhi Suzumiya's mysterious ability to unconsciously alter reality and tries to acquire and study her. Meanwhile, the Magic Side is divided on whether or not she is actually God or a dangerous heretic who must be destroyed. The SOS Brigade and the Kamijou Faction must join forces to keep Haruhi safe and at the same time oblivious to the supernatural.
My Notes: Sadly, this fic hasn't been updated since 2013 and the author hasn't done anything since then, before suddenly adding an epilogue to the last chapter in 2019, but what is already here is golden. It blends the lore so well that the two franchises look like they could exist in the same universe.

A New World A New Way(Pokemon/MLP)
Premise: Arceus, who has been imprisoned for thousands of years is released and does a rapture for all Pokemon and worthy humans to Equss after concluding that Earth was not worth saving and humans are too dangerous to exist(which is why he turns them all into Pokemon upon arrival). The story tells of how Equestria and the world adapts to the arrival of Pokemon and how to move forward, not to mention that many humans brought along are deciding whether or not to accept their fate or defy god.
My Notes: While the story is a good source of drama, it does not for the most have a clear plot or conflict, sure there are fights and clear antagonist every now and them but the story is not as good as it started out. Its biggest accomplishment can be linked to the many spin-off and side-stories made in its liking, not to mention the group dedicated to it which has over 600 members.

The Legend of Roland -
The avatar from the Bender universe of Last Airbender and Legend of Korra and a spartan super soldier from the Halo series. These two seem to have nothing in common, but the contrasts actually are great fun to see given they actually have similar roles and histories but contrasting worlds. The Avatar is a super human by magical means and is trained from youth to function as a peacekeeper in alternating times of war and peace. A Spartan meanwhile is a super human by science and trained from youth to function solely as a living WMD in a war heavy setting. One uses magical elemental attacks and spiritual means, the other has superhuman physicality and technology. But at their core, both are still human even if their roles or societal expectations ask them not to be. That's the sort of compare and contrast we get here in this story where a spartan named Roland (and we later find, others) gets flung into the Bender universe at the time of Legend of Korra Season 1, joining the cast. Relationships get shifted, events play of differently, and a lot of focus is given to someone born from war being now forced into a civilian life. I could nitpick on pacing a few times or some twists being predictable, but I have no real complaints. Fire at will Roland and literally fire at will Korra!

Hasbro'verse (All of It) -
I do love me some mythology gags and this series takes it up a notch. In a nutshell, G1 is G4's ancient past. This not only opens up fun additions like Meghan Williams being the one who helped raise Celestia and Luna, being remembered in legend by the modern G4 cast as a supernatural entity with incredible powers, but also lots of fun when the two rosters meet up. The rainbow bridge of G1 was reconnected and Equestria, formerly Rainbow Valley, has been going through time much quicker than earth. So whereas a decade or two have passed on earth, thousands of years have gone by in Equestria until the reunited bridge synchronized the two again. So Meghan, Molly, and Danny are all still alive and have kids of their own, and travel back and forth is easy as 1, 2, 3. It's also a little known fact that many 1980s Hasbro cartoons like Transformers, GI-Joe, Inhumanoids, Jem, and the like are all subtly implied to take place in the same universe. This is the case here, opening up greatness like the Mane 6 taking a tour of Autobot city while the US president, a former Joe, pleasantly works out friendly relations with Equestria.

And best part? The sequel has a fanon series I'm not too fond of invading Hasbro'verse Earth and Equestria, leading to a mass response from all sides to answer the call to arms to defend each other.

The Lost Hero -
What's not to like about Superman? It's a person with incredible power who never abuses it and could easily be seen as both the codifier and ultimate superhero. And what's my friend Ulti do here? He distills him and makes an original story with the Big Blue Boyscout becoming the Stallion of Steel. Does it have him completely outclassing the pony cast and acting extremely out of character multiple times to make him look cooler (like another superhero crossover I could mention from someone else...)? Heck to hay no! The Lost Hero is just a fun ride that doesn't take too long to read through and clearly shows the author knows a ton of the mythology for both series. While some may say its size lessens its grandness of scale, I instead say it avoids the bloat many other crossovers find themselves bogged down in. Check it out boys and girls!

Honorable Mention -
Power Ranger/ Kamen Rider - Dino Thunder and Dragon Knight Team-Up
I'm a sucker for good Toku series and while Japan has had multiple crossovers between its big two franchises with Super Sentai (what Power Rangers is adapted from) and Kamen Rider, America never got to enjoy that much. There was one crossover in the 1990s with the original Mighty Morphin' Power Rangers getting an ally in the form of the Masked Rider (Kamen means Helmeted/Masked FYI), which got his own series by Saban adapting the Kamen Rider series RX. However outside of the first appearance, the Masked Rider was never seen again in Power Rangers and his own show was a continuity reboot. And while the Japanese series got up in down in quality, Saban's Masked Rider definitely wasn't very good and the brand wasn't adapted again by them.

Flash forward to the 2009 however and CW4Kids adapted the series Kamen Rider Ryuki into Kamen Rider Dragon Knight. Dragon Knight was actually pretty damn good, many Toku fans considering it even better than Ryuki and it was popular enough to be dubbed into Japanese and get merchandise in Japan. The sad part was it only got one season because the CW was dying at the time and since Power Rangers was owned by a different company, no crossover to be had despite the potential being extremely easy to pull off.

This fic did so by mixing up Dragon Knight with a fan beloved PR season, Dino Thunder. Unfortunately it wasn't ever finished and cut off JUST before the two hero teams could properly meet. Talk about a buzzkill...

Unfamiliar (The Familiar of Zero / PROTOTYPE)
Premise: Louise summons Alex Mercer as her familiar. This is an alternate history of the Familiar of Zero world that had been ravaged by plaguebearers in the past, so Mercer's abilities cause quite a bit of fear.
My Notes: Sadly, this fic stopped being updated in 2012, and the author eventually declared in 2017 that they are completely uninterested in updating it and to stop asking them to. Still there are 12 chapters of goodness to check out. Alex is a Showy Invincible Hero and I love it. Alex uses Louise as his link to his humanity just like he did with Dana and he will do everything to protect her. The characters are all a lot more competent than in canon, even Guiche.
Update: An anonymous author has continued the story here.

The Red Knight of Remnant (RWBY / Fate/Stay Night / Fate/Apocrypha)
Premise: To amuse himself, the dimension master Zelretch causes Mordred, the Knight of Treachery, to appear in Remnant, roughly six months before Season 1 of RWBY starts. She befriends Jaune Arc and with nothing better to do, trains him. Six months later, the result is a battle-ready Jaune who doesn't need to fake his way into Beacon. Mordred applies to Beacon along with him.
My Notes: The author has caused a bit of fan backlash because although Pyrrha is part of Jaune's team, Mordred is also on his team and is confirmed to eventually be Jaune's love interest. Also, Mordred, being a Servant, is so powerful that she does not need her Aura to be unlocked to fight Grimm and Hunters; in fact, the author is adamant that her Aura not be unlocked lest she become a Story Breaker Power. I like how just like in her home series, Mordred sometimes shows that deep within her harsh exterior, she truly does care and just wants to be loved. Also how Jaune gets more and more badass, though he still gets his Butt Monkey moments.

Fate/Long Night (Fate/Stay Night / A Song of Ice and Fire)
Premise: After Saber destroyed the Holy Grail in the 4th War (Fate/Zero), something hijacks the ritual and kills Angra Mainyu. When the 5th War begins, it is no longer the Holy Grail War, but the Trial of Seven, where the victor decides which god gets to rule over all creation. The seven Servants who are summoned superficially resemble the seven usual classes: Archer, Lancer, Saber, Berserker, Caster, Rider, and Assassin, but in reality, they are each Champions of the deities who make up the Faith of the Seven: The Maiden, The Smith, The Warrior, The Mother, The Father, The Crone, and The Stranger. However, after all seven have already been summoned, Shirou Emiya still summons Saber.
My Notes: I just have to say Robert Baratheon absolutely steals the show when he shows up, and his interactions with his Master Illya are pure gold. A running gag is all the A Song of Ice and Fire characters mistaking Saber for a Lannister because of her looks. Another one is Rin refusing to listen to her Servant, who is Brandon Stark/Bran the Builder, whenever he tries to explain things like that this is no longer the Holy Grail War and that the Servant classes are different (for example, he is The Maiden's Champion, but she adamantly calls him Archer), meaning different tactics are needed.

Death's Secret Army (Supernatural / Bleach)
Premise: During Supernatural's Season 9, shortly after Kevin Tran was killed, Death, who is one and the same with the Soul King, orders the Shinigami to assist Dean Winchester against the evil angels. Unfortunately, this is happening at the same time as the Shinigami's war against the Vandenreich, meaning their resources are stretched thin. In addition, the forces of Hell take great interest in what is going on.
My Notes: Dean has ship tease with Nanao Ise, which is kinda cute. What's really cool is how the author manages to fit Supernatural and Bleach in the same universe, with certain events in one series affecting events in another. For example, Ichigo and his friends invading Hell in the fourth movie provided the distraction needed for Castiel to rescue Dean from Hell in the Season 4 opening.

Fate Parallel Fantasia (Mega crossover)
Premise: The 5th Holy Grail War starts, but every time a Servant is summoned, another Servant of the same class appears nearby. Instead of a historical or mythological figure, these Servants are characters from other manga and anime. The other characters refer to these as False Servants. False Saber is Kiyomasa "Crow" Senji from Deadman Wonderland, False Archer is Homura Akemi from Puella Magi Madoka Magica, False Rider is San from Princess Mononoke, False Berserker is Scar from Fullmetal Alchemist, False Caster is Lina Inverse from Slayers, False Lancer is Rei Ayanami from Neon Genesis Evangelion, False Assassin is Ryougi Shiki from Kara No Kyoukai, and False Avenger is Akito Sohma from Fruits Basket. Crow and Homura partner up with Shirou and Rin alongside Saber and Archer, but the other False Servants partner with other characters. Add in the manipulations of Kirei Kotomine, Gilgamesh, and Zouken Matou, and this war is total chaos where anyone can die.
My Notes: The author has a real gift for getting into the heads of every character and making them sympathetic, and you're likely to miss them when they die.

The First Remnant Holy Grail War (RWBY / Fate/Stay Night)
Premise: Set during Volume 3, Weiss Schnee attempts to practice her ability to summon familiars like her sister Winter can. She inadvertently summons Servant Saber, Arturia Pendragon. Both parties struggle to make sense of this, especially since Saber did not receive any knowledge of the world she was summoned to, meaning she knows nothing about how Remnant works. But then more Servants start getting summoned by other people and the Holy Grail War is on.
My Notes: It's just adorable how dedicated Saber is to protecting Weiss, and how Ruby befriends her with food.
Note: The author canceled and deleted the story, but it can be found here or here.

Fates Collide (RWBY / Fate/Grand Order)
Premise: Set between Vol 1 and 2 of RWBY. Team RWBY, Team JNPR, Glynda Goodwitch, Cinder Fall, Mercury Black, Emerald Sustrai, and Neo (the four criminals are pretending to be students) decide to spend summer vacation over at Chaldea Academy in the Kingdom of Apocrypha, with Glynda becoming a substitute teacher and the students taking classes.
My Notes: It's just awesome how the author can fit the Nasuverse characters into the RWBY universe while keeping their powers intact. The RWBY characters learn much and make great friendships, though this is Cinder's plan, to learn Chaldea's unique techniques to make herself more powerful. Sadly, the author makes a lot of spelling and grammar mistakes, but it's still understandable. I also made a TV Tropes page for it: Fates Collide.

RWBY Zero (RWBY / Fate/Zero / Fate/Stay Night)
Premise: Saber/Arturia Pendragon woke up in Remnant when she was forced to destroy the Holy Grail and end the 4th Holy Grail War. She moved on with her life, got married, and had a son, Jaune Arc. Years later, she visits the Vytal Festival to see how her son and his friends are doing. But she can't run from her past forever. Old enemies emerge, and a new Holy Grail War happens.
My Notes: It's sad that Arturia was a decoy protagonist, as she eventually gets killed and Team RWBY and JNPR take over, but the sheer amount of character development everybody gets is amazing. Especially after everyone summons their Servants. Even freaking Adam Taurus becomes more 3 dimensional.

The Vasto of White (Bleach / Fate/Stay Night)
Premise: Shirou Emiya dies and becomes a Hollow, but he retains his ability to Trace weapons and his heroic nature. He eventually unites Hueco Mundo under his leadership and aims to protect the Hollows from their enemies.
My Notes: It is very interesting how the author handles what happens when a Zanpakuto is Traced.

Fate: Desiderantes Affectibus (Fate/Zero / Puella Magi Madoka Magica)
Premise: Kariya Matou summons Sayaka Miki as Berserker. Sayaka only goes crazy when she is fighting, and is benevolent towards him. With a much more compatible Servant, can Kariya win the Holy Grail War and rescue Sakura, or will he and Sayaka be doomed to suffer a tragic ending?
My Notes: Sayaka's interactions with everybody are adorable.

The Fifth Holy Grail War: A Pony's Perspective (My Little Pony: Equestria Girls / Fate/Stay Night)
Premise: When Sunset Shimmer abandoned Princess Celestia and jumped through the mirror, she landed in Fuyuki City and eventually became a student in Shirou Emiya's school. Later, Sunset steals Twilight Sparkle's Element of Magic crown and Twilight and Spike pursue her through the mirror. Twilight soon meets Shirou, just as the Holy Grail War starts.
My Notes: There is some artistic license like how Twilight can communicate with the humans even though Fuyuki is in Japan, but the author probably decided having a language barrier would complicate things. What's cool is that since the world of Fate/Stay Night has magic, Sunset and Twilight still have their powers. Shirou takes Flash Sentry's place and Sakura Matou takes Fluttershy's place. Also, Sunset becomes the Master of Caster and the three Sirens are here too. Twilight becomes the Master of Assassin Jack the Ripper, Sakura summons Rider Astolfo, who knew the Sirens back when he was alive, and Zouken summons Avenger Jeanne d'Arc Alter.

Daily Equestria Life With Monster Girl (My Little Pony: Friendship Is Magic / Daily Life With Monster Girl)
Premise: Centorea Shianus, the friendly centaur and one of Kimihito Kurusu's harem members, somehow gets transported to Equestria and lands in a rural town. Unfortunately, since the only centaur the ponies know of is Tirek, they automatically assume Centorea is evil and imprison her. Due to a language barrier, Centorea cannot communicate with them and only wants to return home to her love and her friends.
My Notes: It's interesting how this misunderstanding can happen and it is logical. We also see the Humans Are Ugly trope: the ponies find Centorea's appearance very uncanny; her horse body is beautiful to them but her human body is a hideous deformity.

The Power of Choice (Godzilla / RWBY)
Premise: During Godzilla: Final Wars, Gorath, the asteroid containing Monster X, misses Earth and eventually lands in Remnant. When he frees himself, Monster X realizes he is finally free from his Xillian masters and decides to live his own life. But it's not that easy. The humans mistake him for a Grimm (since his pitch black hide and white bone armor makes him look just like one) and Salem becomes determined to destroy this third party to her plans.
My Notes: Though this story is not connected to The Bridge, the author based Monster X's personality on The Bridge's X as a homage. It's awesome how he changes things and interacts with everyone, and kicks Grimm ass. Then more Kaiju come. The fic was eventually canceled, but received a remake.

RWBY: Epic of Remnant (Fate/Grand Order / RWBY)
Premise: In the final battle against Tiamat in Babylonia, Gudako and her Servants Angra Mainyu, EMIYA Alter, Berserker Lancelot, and Hassan of the Cursed Arm fall into the Black Mud and are somehow transported to Remnant, a few days before Volume One starts. Gudako goes into a coma and her Servants are turned into teenagers. Ozpin finds them and the Servants reluctantly agree to join Beacon Academy in exchange for Gudako getting medical attention.
My Notes: As usual, we get a lot of misunderstandings, like when Angra Mainyu tells Ozpin they were fighting a woman with black mud that spawns monsters (Tiamat), Ozpin thinks he was talking about Salem. The Servants don't like being teenagers again, but get character development and make friends, and EMIYA Alter's friendship with Ruby Rose is adorable. Salem detects them and becomes a Yandere for Angra Mainyu, seeing him as a being similar to herself, and tries to get him to join her. Fortunately, Angra Mainyu may hate humanity, but he loves Gudako more. Then we learn six other Servants fell into the mud and have also arrived in Remnant in different areas.

Pokémon Let’s Go! Woona version (My Little Pony: Friendship is Magic / Pokemon)
Premise: Princess Luna abruptly wakes up in the world of Pokemon in her filly form and finds that while she can talk to Pokemon, to Humans, she can only say "Woona". Mistaken for a Pokemon, she is caught by Red and struggles to make sense of what is going on.
My Notes: While Luna definitely doesn't like what she perceives as slavery, she starts to adjust, enjoy battling, and befriend Red and other Pokemon.

Little Lost Raichu (My Little Pony: Friendship: Is Magic / Pokemon)
Premise: An amnesiac Raichu wakes up in the Everfree Forest and is rescued and taken in by the Mane Seven. After recovering, she is determined to repay their kindness.
My Notes: This story has a lot of sequels, like Raichu for Hire, Little Lost Pikachu, A Little Adventure in Alola, and Chu and the Storm. What I really love is that the Raichu, named Nica, once she is able to communicate, addresses the general incompetence of the Royal Guard and helps every character she meets learn how to defend themselves.

Along Came an Arachne (My Little Pony: Friendship is Magic / Daily Life With Monster Girl)
Premise: Rachnera Arachne, the friendly and mischievous spider woman and one of Kimihito Kurusu's harem members, somehow gets transported to Equestria and lands in a rural town. While she frightens the ponies at first, she slowly befriends them, and when children are kidnapped by the Changelings, she sets out to rescue them, and hopes she will eventually find a way to return home to her love and her friends.
My Notes: The premise is similar to Daily Equestria Life With Monster Girl , but with a friendlier reception from the locals, as many of them are farmers who respect spiders. Interestingly, the fic starts several years before the series starts, as the family Rachnera stays with is Sunset Shimmer's family, and they mention she recently became Celestia's student.

Can't believe I didn't mention this one yet.

Lost to Dust (RWBY / Fate/Grand Order)
Premise: This is a sequel to Fates Collide. One year later, Team RWBY goes on separate but interconnected adventures. Cinder Fall and her assistant Chloe von Einzbern try to find the other three Maidens of the Seasons. Meanwhile, a mysterious third party is attacking both Ozpin and Salem's forces.
My Notes: Just like the first story, I love how the author is able to fit the Nasuverse characters into the RWBY setting. I also made a TV Tropes page for it: Lost to Dust.

Fate Grand Order: Slayer Chronicles (Fate/Grand Order / Doom Eternal)
Premise: When the Incineration of Humanity begins, Ritsuka Fujimaru and her male counterpart Gudao are both humanity's last Masters. Gudao is partnered with Mash Kyrielight, while Ritsuka is partnered with the Doom Slayer and VEGA.
My Notes: The Doom Slayer's presence starts changing things, like when during Septem, they get the Night Sentinels on their side.

A Certain Magical Pokemon Index (A Certain Magical Index / Pokemon)
Premise: A remake of the cancelled fic A Certain Pokemon Index with a similar plot, where Touma Kamijou starts his Pokemon journey with no Pokemon but accompanied by Index as his living Pokedex. Mysteriously, he sees certain Pokemon as girls wearing costumes (for example, a Pikachu is Mikoto Misaka, an Eevee is Shizuri Mugino, and a Caterpie is Kazari Uiharu), while most, but not all people simply see them as ordinary Pokemon.
My Notes: It is very clever how the author fits each character to the Pokemon. Uiharu as Caterpie is one of the most adorable things ever.
Edit: To my great regret, the fic has disappeared from the Internet. I have messaged the author, Yue Yun, asking what happened to it, but I have not gotten a response. However, the chapters can be downloaded here.

Tempest (Ben 10 / Fate/Apocrypha)
Premise: While battling some magical villains, Ben Tennyson's Omnitrix is damaged, trapping him in Frankenstrike's form. Then he is thrown through a portal and lands in an alternate world when he is found and nursed back to health by the female Frankenstein's Monster. She thinks he is the husband Victor Frankenstein promised her, and the misunderstanding is sustained because they cannot speak each other's language.
My Notes: Warning; this fic has violence, gore, nudity, and sex scenes. If you can handle that, little Fran-chan is adorable.

Avenging Class (Marvel Cinematic Universe / Fate/Grand Order)
Premise: During the final battle against Loki and the Chitauri in The Avengers (2012), Mysterious Heroine XX arrives and helps out. When she finds she can't leave, she joins the Avengers.
My Notes: It is awesome how XX changes things, like getting Sif and Karl Mordo to join the Avengers and getting the Avengers to help out during Iron Man 3. Her interactions with Queen Frigga leave a warm and fuzzy feeling inside.

Boldores and Boomsticks (RWBY / Pokemon)
Premise: Ultra wormholes start randomly connecting Remnant and the Pokemon Earth, and Salem starts sending Grimm through to investigate. Team RWBY falls into one and lands on Earth. Now they must figure out this new world and help the natives defend themselves from the Grimm.
My Notes: Culture clash is one of the funniest things. This Earth is the anime, and a lot of familiar characters like Professor Oak, Gary, and Tracy show up. Casey, the girl obsessed with the Electabuzz baseball team, becomes a major character. Interestingly, the author insists that Ash Ketchum will never show up in person, even if characters often mention him and his feats.

Zero to Hero (Fate/Zero / Dragon Ball Z)
Premise: In the Fourth Holy Grail War, Waver Velvet summons Goku as Rider (since he uses the Flying Nimbus and Power Pole, everyone thinks he is the Monkey King) and Kirei Kotomine summons Mr. Satan as Assassin. They start driving everyone crazy.
My Notes: This is really hilarious because these two have no sense of subtlety and their Masters can barely control them. Since Servants are powered by belief, Mr. Satan is extremely powerful, plus he can briefly summon Majin Buu.

Playing with Dolls (Black Rock Shooter / A Song of Ice and Fire)
Premise: Hundreds of mysterious sleeping women descend onto Westeros. Nicknamed Dolls because of their otherworldly beauty and agelessness, they only awaken when someone worthy approaches them, then they serve that person. Strength serves Jon Arryn, Black Gold Saw serves Tywin Lannister, and Black Rock Shooter serves Ned Stark. The Game of Thrones is forever changed.
My Notes: Since there are supposed to be hundreds of them, many of the Dolls are OCs. Arya Stark hero worshiping Black Rock Shooter is adorable.

Between Walls of Ice and Ships of Steel (A Song of Ice and Fire / Arpeggio of Blue Steel / Black Rock Shooter)
Premise: Several members of the Fleet of Fog find themselves in Westeros. Using their Mental Models to pass for human, they claim to be House Kirino and become House Lannister's allies while playing the Game of Thrones. Meanwhile, the Others try to summon beings from other worlds to assist them, but get characters like Dead Master, Black Gold Saw, and Chariot who start attacking and subjugating them.
My Notes: Several Fleet of Fog members are OCs. Since Tyrion becomes a major link to and eventually marries one of them, he gets a lot more respect from his father. There are a few changes from cannon, like Jon Snow is the son of Ned Stark and Ashara Dayne.

Nihilus Filius Et Sacerdos (Yu-Gi-Oh! Card Game / A Song of Ice and Fire franchise during the time period of House of the Dragon)
Premise: Dogmatika Ecclesia the Virtuous, Fallen of Albaz, Tri-Brigade Mercourier, and some of their Springan allies find themselves in Westerios and are taken in by Corlys Velaryon and his family. Everyone is intrigued by Ecclesia and Albaz's abilities and these kids will get caught up in the Dance of the Dragons.

Dueling Zero (Yu-Gi-Oh! Card Game / Fate/Zero)
Premise: Each Master summons a Duel Monster spirit. Tokiomi Tohsaka summons Maiden With Eyes of Blue as Archer, Kirei Kotomine summons the woman in Forbidden Chalice, Forbidden Lance, Forbidden Dress, and Forbidden Scripture as Lancer, Kiritsugu Emiya summons Sky Striker Ace - Roze as Rider, Kayneth El-Melloi summons Metal Reflect Slime as Caster, Waver Velvet summons Marauding Captain as Saber, Kariya Matou summons Dragon Core Hexer as Berserker, and Ryuunosuke Uryuu summons Number 96: Dark Mist as Assassin. Dogmatika Ecclesia the Virtuous later appears as Ruler. The being who inhabits and corrupts the Holy Grail is The Wicked Avatar, who starts out as Pretender but then becomes Beast.

The legendary Saiyan in a fairy's world (Dragon Ball Super: Broly / Fairy Tail)
Premise: When Cheelai wishes for Shenron to save Broly from Gogeta, the dragon grants it by transporting Broly to Earthland. He adjusts to his new surroundings and starts changing several people's fates.