It's one of the most prevalent discussions among card game anime enthusiasts: Yu-Gi-Oh! versus Yu-Gi-Oh! GX. Well, at least it was, until there were six different Yu-Gi-Oh! anime to choose from, and the conversation became much more complicated.
Nevertheless, when pitting Yu-Gi-Oh! -- aka Yu-Gi-Oh! Duel Monsters, to differentiate it from the 1998 Toei anime -- against Yu-Gi-Oh! GX was the cool thing to do, many fans were steadfast in their belief the spinoff was no match for its predecessor. And to this very day, many old-school Yu-Gi-Oh! devotees still hold up the original adventures of Yugi Muto and his friends as the franchise's gold standard. However, now that we have the power of hindsight, there's an argument to be made that GX is actually the stronger of the first two shows.
As fun, and as iconic, as the original Yu-Gi-Oh! series is, a big part of the reasons it tends to be put on a pedestal comes down to nostalgia -- particularly, nostalgia for the earlier seasons. And therein lies the major reason why GX is arguably the better of the two series: Yu-Gi-Oh! peaked too soon, whereas GX only got better as time went on.
As far as anime that exist to promote trading cards go, Yu-Gi-Oh! GX was a masterclass in slowburn character development. By the time the series ended, the characters were entirely different people than the were when we first met them. And we got to see that process unfold in real time, watching them slowly grow, learn and ultimately change over the course of their time at Duel Academy -- with series protagonist Jaden Yuki/Judai Yuki having the most profound evolution.
While series protagonist Jaden Yuki/Yuki Judai easily had the most profound evolution, most of GX's characters -- be they main or supporting -- were also given intriguing arcs and motivations that spanned multiple seasons. They really felt like high school kids who were slowly getting to know who they really were over a four-year period.
Yu-Gi-Oh! gave meaningful arcs to major players like Yugi, Yami and Seto Kaiba. However, its supporting characters didn't get quite as much development over the show's five seasons, save for a few life lessons and big moments here and there. Sure, some GX characters fell by the wayside as well. But whereas GX made it a point to ensure its characters were continually evolving, Yu-Gi-Oh! was often hesitant to disrupt the status quo.
The voices, mannerisms and strong personalities of Yu-Gi-Oh!'s original cast will rightly live on in the hearts and minds of fans forever. Still, it's GX's cast who feel more like genuinely fleshed out individuals. The seemingly innocuous "filler" stories from early in GX's run ended up being anything but, as they underscored the show's devotion to really exploring what made its characters tick -- which is ultimately the reason GX was able to surpass its predecessor.
Each season of GX was better than the last, with each school year exponentially raising the stakes and forcing the students to adapt. In fact, Season 4 was such a fulfilling payoff it's honestly a shame so many casual fans never got to see it, considering it was the only season of GX not dubbed into English or broadcast on American television.
Yu-Gi-Oh! GX peaked when it was coming to a close and its characters were fully-realized, making the whole experience feel like a worthwhile journey. Yu-Gi-Oh! Duel Monsters, on the other hand, really sort of hit its apex at the end of Season 3, with the following two seasons not quite being able to recapture the magic that won over a generation of duelists.
Season 4 certainly had its fair share of good ideas and great moments, not to mention new characters who were much more interesting than they were given credit for (even if they weren't particularly memorable). And while the first half of Season 5 just felt like treading old ground, it still managed to kick things into high gear in its second half and end the series on a high note.
Even so, the fact remains that while late GX continually upped the ante and took its story and characters to new heights, late Duel Monsters mostly felt like a shadow of its former self. When talking about their favorite moments from the original show, there's a reason a lot of OG Yu-Gi-Oh! fans tend to bring up Duelist Kingdom and Battle City, and not the Orichalcos Saga or the Kaiba Corp. Grand Prix.
At the end of the day, Yu-Gi-Oh! GX is the championship duelist who retired on top, while Yu-Gi-Oh! Duel Monsters is the former champ who kept going well past their prime.