In Yu Gi Oh 5D's the bridge that was built to try and connect Satellite and Neo Domino City was known as the Daedalus Bridge. In a Greek myth Daedalus, along with his son Icarus tried to escape a prison on an island by making wings out of wax and feathers and flying away. However, while they were in the air, Icarus flew too close to the sun, his wings melted and he fell down into the sea. Now, who else do we know that flew too close to the sun and fell?
So in the second season, everyone is running around trying to earn money with odd jobs, which at first made me wonder "what the heck happened to Jack's money from season one". Sure he lost his sponsers but he still should have had money left over. Then it dawned on me. THAT'S how they paid to build that bridge, they used up all of Jack's money!
I recently had an epiphany that made Yu-Gi-Oh! 5Ds about ten times more heartwarming. The realization was: the concept of "family" in Satellite is the same as the concept among gargoyles. In a world where survival is such an uncertain thing and the likelihood of parents not outliving their offspring's childhood is high, blood ties get disregarded. It's just not a viable way for their society to function, so they don't form bonds based on blood any more than gargoyles care about whose biological offspring their clan's hatchlings are. Circumstances have forced "families" to form in other ways, or no one would survive. People like Martha, Pearson, and Crow aren't just Parental Substitutes — they're parents.
Early in 5Ds, Rex Godwin says something to the effect that he'll make any sacrifice necessary to save the world. At the time it seemed like the "sacrifice" he referred to was Satellite, but thinking back on that line after the Dark Signer arc, it becomes clear that he was talking about sacrificing the entire planet.
On a similar note, I was wondering why Z-One would trigger Zero Reverse by telling Rudger to look into the old Momentum, knowing that it would release the Dark Signers/Earthbound Immortals, who had a 50-50 shot of destroying the world, which is what Z-One wanted to prevent. Rex, all the while, is encouraging the Signers to defeat the Dark Signers, and then he becomes one himself, wanting to destroy the world and build a new one. Why would Z-One allow this? But then I realized something. Rex was seen talking to a shadowy figure long before becoming a Dark Signer, just like the one that talked to Rudger. What if this figure was also Z-One, and Rex's plan to recreate the world was just another of Z-One's attempts to save the ruined future? This theory was almost cemented in my mind when Z-One's backstory is given in 149, and his computer with the research on Yusei only lists five Earthbound Gods, not seven, which suggests that Rex never became a Dark Signer in Z-One's timeline.
Which, in turn, touches on another interesting point; the earliest shown changes by Yliaster take place at the time of Momentum's development, and I think they once mention Yliaster having orchestrated Zero Reverse (if I'm wrong, please correct me on that point). In the original timeline, if Zero Reverse didn't happen, it's possible that Satellite and the City were separated by a different means (perhaps an actual tectonic shift, like they covered the accident up with - either that, or Satellite was simply a disadvantaged area of the city) which also released the Earthbound Gods. However, if Zero Reverse didn't happen, it's entirely possible that Rudger didn't turn evil (however, he may have died in an unrelated way, to allow for the same Signers in the previous timeline), and therefore Rex didn't lose him to the ministrations of fate, meaning that his loneliness wouldn't have driven him to look into the myth of the Signers. BOOM; two Dark Signers gone.
Card games on motorcycles. How stupid is that? Well, when you think about it, it's actually not that silly; the motorcycles (along with most everything else in Neo Domino City) is powered by Ener-D. Ener-D has recently been revealed to be duel energy. So, in essence, fitting vehicles with the ability to duel on them is like fitting them with their own self-powered generator.
Lets be honest, the series was teasing biker duelists since Yugi's day. Combining the two was just the next logical step.
The initial four Signer Dragons all reflect the character of their user. Stardust Dragon sacrifices itself to protect other cards from destruction and then returns to the field, in the same way Yusei is always putting himself at risk for the sake of his friends, and in his duels constantly gets pounded but gets back up to keep fighting. Red Dragon Archfiend destroys all the opponent's defense monsters when it destroys one of them, and destroys its owner's monsters that didn't attack, reflecting Jack's ruthlessness, devotion to power, and the betrayal of his friends to succeed. Black Rose Dragon destroys all cards on the field and saps the attack of enemy monsters to zero, representing Akiza's initial character traits, namely her borderline Omnicidal Maniac tendencies and love of causing pain and suffering. Ancient Fairy Dragon allows the special summoning of monsters and recycling of Field spell cards, reflecting Luna's bond with duel monster spirits and their world.
Life Stream Dragon's effect to restore and protect the life points of the player and their allies is a pretty good reflection of Leo's desire to protect Luna above all else.
Bit of Fridge Brilliance from this troper related to 5Ds: Bruno has no eyeshine. Usually, when a character has no eyeshine, it means either they're background and the artist was being lazy, or that their "spark of life," as one of this troper's friends called it, has gone out. Considering that Bruno is a robot this makes PERFECT SENSE.
Re-watch the scene in GX when Darkness shows Judai a vision of the future. Seem familiar?
Here's one people do not seem to have noticed. All this plot armor, which becomes especially evident against Team Unicorn (but also affects other duels, which are interrupted before their obvious finish, like the one against Sherry)? It is because Signers cannot lose against non-Signers (or people with similar powers, like Team Ragnarok or Yliaster ,anyways), so it is actually justified, even if it is somewhat unsatisfactory, and creates no plot hole or idiot ball, just the orders of fate.
More Fridge Hillarious, but if you look at the way Jose mounts his Duel Runner, in order to do so without revealing he's a [[spoiler cyborg]] he'd have to either sit in it backwards or lie down like on a toboggan.
In the card game, Rex's two ace monsters were changed to both require a specific Tuner monster, and any amount of non-Tuner monsts whose levels total 5. This makes them something of an Evil Counterpart to Yusei's Warrior Synchro monsters.
Individually, Yusei's monsters are weak to the point of derision, but Yusei uses them as a Synchro version of a weeny-rush deck. note An archetype that relies on special summoning and combining low-level monsters to overwhelm an opponent with more powerful monsters. Hitherto, it was used by exactly one anime character precisely because it isn't flashy.
Remember Joey's cousin from the street duels? The fact that he looks exactly like Joey imples that he is the same age that Joey was in the original series, which allows us to guess at how much time has passed since then. Joey was sixteen in the original series (according to the Yu-Gi-Oh Wikia anyway.) If Joey's cousin wasn't born yet in the original series (which might be assumed from the fact that Joey never mentioned him), that would mean that fewer than sixteen years have passed since the original city. In other words, the Yu-Gi-Oh world went from a reasonably peaceful place to a socially-stratified world defined by a grossly unequal caste system, complete with a police force whose sole purpose seems to be maintaining the oppression of the lower caste, in fewer than sixteen years. Suddenly that throwaway gag involving Joey's doppelganger doesn't seem so funny anymore.
Considering Ushio is still alive...
It's worse, GX was 10 years after DM, and everything was still cool. So that means everything went to shit in less than SIX.
Given that we've been told Zero Reverse happened roughly 16-17 years before the main plot of 5D's, Zero Reverse should've happened some time during the Battle City Tournament! Considering that during Zero Reverse, there was a quite fierce storm, and during the Battle City Tournament, there were some quite fierce storms too, every time Slifer or Ra showed up, there might be some truth to those claims... Though not a single building was destroyed during the Battle City Tournament (not counting Noah's island, since that was filler)...
However, this might not be the case. First, "cousin" can mean a first cousin, or a second cousin, and maybe even removed by a generation or two. It is never stated how far in the family tree Jesse is from Joey, just that they are cousins. Second, Jesse does not resemble his relation too greatly, with the hair being the primary defining feature. Jesse's face is much more angular, and they have different eye colors. Joey and his family have the defining trait of brown eyes, while Jesse clearly has blue eyes. Potentially, due to the lack of any youthful softness like Joey's face, Jesse may also be older. Therefore, using a throwaway gag from the dub as a way to figure out how fast Neo Domino collapsed is much more difficult and implausible than it really is.
However, at the very least, we can assume that Ushio was a former classmate of Yugi's since the name is the same and he looks like an older version of the guy from chapter 1 of the manga. He also looked to be middle-age, maybe around 50 or so. So 5D's roughly took place 20 years or so after GX (and 30 after the original series). That means that Zero Reverse occurred soon after the end of GX, which certainly would give enough time for Synchro Monsters to be developed.
Relating to the Machine Emperors/Meklords: It's heavily implied that if the duelist loses to any of them while their synchros are inside it, they're possibly gone for good. For instance, Ushio's synchro is never seen used again since Wisel's debut (implied to have been pulled in by its effect), Yusei and the twins are desperate to get their dragons back before their life points are gone, and it is mentioned the synchro summoning style is what caused things to hit the fan and want them gone. It seems natural that the synchros stay captured if the duelist loses or worse.
Especially when you consider that most monsters are sentient in this franchise...