Therefore... "Let's Do the Time Warp Again"!
Despite Saint Seiya ending via cancellation in late 1990, with its proper final chapter even being used to entice people to buy the debut issue of V Jump, it never truly left public consciousness in Japan during the 90s. There was a Game Boy game in 1992 based on the trading card game from Bandai, the manga got re-released by Shueisha in aizouban format from 1995 to early 1997 (while Kurumada was making B't X for Kadokawa Shoten), and in 1996 the band Make-Up temporarily reunited to produce a new Seiya-themed album; not a lot, sure, but just enough to keep it in the memory of fans. Therefore, when Masami Kurumada returned to Shueisha for Ring ni Kakero 2 in 2000 it didn't take long for Saint Seiya to also come back, in some form. It all started with a two-part side-story novel written by Tatsuya Hamazaki & Toei finally starting its anime adaptation of the Hades Chapter in 2002, followed by a manga spin-off/prequel by Megumu Okada, and in 2004 it (kind of) culminated in Saint Seiya Tenkai-hen Jousou ~overture~, the fifth anime movie for the franchise. However, unlike the non-canonical movies from the 80s, this was literally meant to be the "overture" to the next part of the canonical Saint Seiya storyline: The Heaven Chapter. Unfortunately, the end result seemingly did not conform to the story that Kurumada himself had wanted to tell, so the plans for a TV anime that continued off of the fifth movie were scrapped (plus a bunch of other shake-ups regarding staff & cast that I've covered elsewhere) and Kurumada decided that he would instead continue the story of Saint Seiya on his own in manga form, eventually removing all canonicity of the Tenkai-hen movie.
The end result of that whole ordeal, then, was the debut of Saint Seiya: Next Dimension - Meiou Shinwa/Myth of Hades in Combined Issue #22 & 23 of Akita Shoten's Weekly Shonen Champion magazine in 2006. Likely part of the reason for this shift in publisher, aside from the fact that Kurumada had already been working with Akita Shoten for said spin-off manga of Seiya, was because Kurumada had decided to make his Seiya sequel manga in full-color, due to advancements in computer coloring technology, though this did pretty much make it nigh-impossible for Kurumada to serialize it in any sort of consistent fashion for a weekly magazine. Not just that, but the initial chapters were given even more special treatment by being "sealed" together in each issue of Shonen Champion. For a variety of factors (including possibly complaints from other Champion mangaka, who might have felt jealousy over the preferential treatment) the "sealing" aspect was dropped after Chapter 8 in early 2007 (along with chapters from that point on being ~18 pages each, rather than the 7-8 they initially were), and starting with Chapter 15 in early 2009 the manga would be initially serialized in greyscale (with some exceptions, like certain opening pages or super special scenes), while the collected tankouban would continue to be in full-color. From that point on Next Dimension would continue to come out on a highly irregular basis, though once RnK2 was finished in 2008 it would be the only manga Kurumada was actively making until 2014, when he revived Otoko Zaka for his 40th Anniversary. After that Kurumada would alternate between making a new volume's-worth of ND (which he called "Seasons") & making other manga, whether it be more Otoko Zaka (which he wouldn't finish until late 2023) or a variety of short-run manga & one-shots... all with the hardcore Saint Seiya fans having their patience tested & letting their anger be known online; seriously, some people just need to chill out about comics.
Eventually, though, Kurumada got to the finish line, with the 118th & final chapter of Next Dimension appearing in Issue #31 of 2024 that July, and the 16th & final full-color tankouban coming out later that same year on November 8; in the end, ND averaged ~6.5 chapters, or ~0.89 volumes, per year. Therefore, to finish off this blog's year-long celebration of Masami Kurumada's 50th Anniversary, let's see if the 18-year serialization was truly worth it by reviewing Saint Seiya: Next Dimension... what, Kurumada himself didn't make Ai no Jidai for his 40th Anniversary until mid-2015!
[NOTE: Naturally, there will be spoilers regarding the original Saint Seiya manga. This is a sequel, after all.]