For so many fans, the X-Men: The Animated Series.
Along with the impressive animation style, this series stood out for a few reasons. The overarching storylines were unheard of in a kids show at that time, many of the characters became iconic, and it helped turn the X-Men into household names. With the level of consistency that the series had, it's interesting to see which one ranks as the best.
Season 5 (7.3)
The final season of X-Men: The Animated Series was kind of a mixed bag. At times, it delivered on the high quality that audiences were used to but at other points, it felt like a shell of its former self that couldn't live up to the previous incarnations. "Hidden Agendas" (6.6) and "Longshot" (6.5) didn't score well, while "Jubilee's Fairytale Theater" (5.7) has the lowest rating of the season.
On the other hand, the season got off to a good start. "Phalanx Covenant," adapted from the comic storyline, was a good two-parter to kick things off (8.0 each). The final episode, "Graduation Day" (8.3) scored the highest but it should be noted that that wasn't intended to be the end of the series. More episodes were ordered by the network than expected, leading to the final set of installments being animated differently than the rest, which helped lead to "Graduation Day" as the end. Still, they were mostly in the same vein as the rest of the series, which was welcome.
Season 4 (7.6)
The penultimate season ranks slightly ahead of the last one and a big reason for that is that these were meant to be the way the show wrapped up. The original plan was for the "Beyond Good and Evil" episodes to be the finale and they were met with strong praise (8.2, 8.2, 8.2, and 8.3 for each of the four parts). Those installments saw the involvement of Apocalypse, the return of Cable, and much more from the lore of the comics. It helped make the episodes some of the most beloved of them all. In fact, the episodes that followed seemed to miss the mark.
"Have Yourself a Morlock Little X-Mas" and "Love in Vain" (6.5 and 6.8) were both considered lackluster compared to the rest of the franchise. The season did peak early with the two-part opener in "One Man's Worth" (8.3 and 8.4), which wouldn't be topped at all in later episodes. Season 4 also gets credit for attempting some new things, including storylines for Moira MacTaggert, her son, and most notably, Quicksilver and the Scarlet Witch.
Season 2 (7.7)
Like most of the seasons of X-Men: The Animated Series, season 2 got off to a strong start. "'Til Death Do Us Part" was a two-parter that rated at 8.0 and 8.2, putting it near the top. It set the tone for the rest of the season and saw Cyclops and Jean Grey get married while also bringing Morph back into the fold. The season hit a few rough bumps in the road afterward including "Whatever It Takes" (7.2) and "X-Ternally Yours" (7.1) but things picked up pretty soon after those iterations of the show.
The "Time Fugitives" episodes are among the most lauded of the series, scoring 8.3 and 8.4, as they brought back the aspect of time travel while seeing the return of Bishop and Cable. "A Rogue's Tale" (7.9) was another highlight as it showcased her history with Ms. Marvel. The show hit a relative low point with "Mojovision" (6.3) near the end but picked up for the two-part finale, "Reunion" (7.9 and 8.2).
Season 3 (7.8)
The show displayed some really impressive consistency in its early days, with not much separating the scores in the first few seasons. That was evident with season 3, which is smack dab in between the first and second seasons in of quality. The most memorable arc of season 3 was "The Phoenix Saga." The five-part story all scored well (7.9, 7.8, 8.1, 8.0, and 8.5) while telling the tale of Jean Grey's interaction with the powerful force. The live-action movies have attempted to adapt this arc often but fans feel they fell far behind what this series managed.
The rest of season 3 also showcased some other interesting arcs. There are the "Savage Land" episodes (7.2 and 7.3) and the "Out of the Past" (7.6 and 7.5) opener, plus the one-offs revolving Archangel in "Obsession" (8.1) and Nightcrawler in "Nightcrawler" (8.1), which are both great. The season also returned to the Phoenix arc with "The Dark Phoenix" four-parter (8.0, 8.2, 8.4, and 8.3). It was pretty revolutionary stuff for the time.
Season 1 (8.0)
Almost immediately, X-Men: The Animated Series stood out as something special. The two-part premiere, "Night of the Sentinels" (7.8 and 8.1) was a whole new take on superhero storytelling in animation. Seeing things like Morph's death was way deeper than most shows were willing to go at the time. The season also worked to introduce these characters and their dynamics, including Gambit flirting with Rogue, Jubilee as the new team member, and the love triangle involving Cyclops, Wolverine, and Jean Grey.
The arrival of the show's top villain in "Enter Magneto" (7.8) was good and seeing Wolverine search for solitude in Canada in "Cold Vengeance" (7.9) was certainly interesting. However, the season hit on the highest note when it came time to reach the finale. "Days of Future Past" (8.6 and 8.6) told the iconic arc from the comic books that would later be adapted for a 2014 feature-length film and ended up being the best installments of the series.