A big part of the reason is that Books of Magic was always intended to be an exercise in esoteric geek knowledge. The miniseries was designed as a way to reintroduce readers to all the DC-universe characters with magic-based powers—like the Spectre or Amethyst Princess of Gemworld—following one of its periodic shakeups. Each of Gaiman's four books follows Tim through the past, present, and future of the mystical universe as he visits various realms and meets different magical figures. In this way, The Books of Magic functions as more of an encyclopedia than a story, while Rowling's books offer an elaborate plot complete with original characters.

Gaiman is a deft enough storyteller that Tim isn't just a blank presence—he's more of a snot than Rowling's young wizard, and he has a low-key but ominous taste for power. As a useful stand-in for the reader, Tim is a tourist through eldritch realms of fandom detritus and continuity porn (a comic-geek term that refers to excessive attention to narrative integrity at the expense of the story itself). The books span characters like Zatanna, Zatara, Dr. Fate, and Dr. Occult, organizing all the accumulated layers of DC's corporate property into a solemn wiki-before-there-were-wikis.

Was the potential hit, then, derailed by the possibility of intimidating, Byzantine crossover nonsense? Maybe—though the truth is there's an immense appeal in deeply complex comic-book lore 25 years on. Marvel's ever-popular films and DC's television shows have mastered the art of packaging geek Easter eggs and winking crossovers for a mass audience. In that sense, when Deadman pops up for a cameo in Books of Magic, it doesn't feel dated at all. You might as well be watching The Flash.

For that matter, one of the series' central figures is John Constantine, the cynical working-class, anti-hero magician. After battling baddies in the present, the character shows up as a kind of cosmic fool at the end of time, still mysterious and still as cool as ever while the universe around him experiences heat death. Whether Constantine will actually be around millennia from hence is an open question, but he's survived the quarter century well enough. The first season of Constantine the television series just ended in February.

The Books of Magic could be seen as a failed Harry Potter, but it's perhaps more accurate to view it a dry run for superheroes taking over movie theaters, TV screens, and bookshelves around the world. What was most prescient about the miniseries was the way it combined YA fantasy-adventure and superheroes, two of the most popular genres of the following decades. Harry Potter is essentially a superhero—an adolescent power fantasy functions much the same way whether you're handed a wand or bitten by a radioactive spider. Similarly, superheroes fit well into fantasy-adventure. In Gaiman’s comics, plenty of unspeakable dark forces like Voldemort pop up, as do King Arthur and Merlin. The Books of Magic makes The Lord of the Rings, The Avengers, Harry Potter, and even Twilight all look like entries in the same broad genre of tween-superhero fantasy, in which someone insignificant gets mighty powers, fights the forces of evil, and ultimately triumphs.