Those X-Men investments are paying dividends, and their keys simply owned the secondary market this week.

From 10 days to six months, the X-Men officially ruled eBay. Marvel's Merry Mutants covered the landscape with first appearances and key issues. Why wouldn't that be the case? Deadpool & Wolverine is the talk of the MCU and could very well be the biggest hit of Phase Five. Then there's X-Men '97, which has given fans the X-Men adaptation they've always wanted. Put it all together, and it makes for a hot X-market.

Don't forget that these rankings are not about the fair market values. The Hottest Comics sort the top-100 single issues across eBay. Rather than focusing on the FMVs, this list is ordered by sales volume, combining both the raw and graded sales.

10 DAYS

18. X-MEN #94 (+82)

As X-Men '97 captivated audiences with another strong episode, those key issues were soaring higher than Archangel's wings. It was only fitting that one of the most significant issues in the series' history was at the forefront.

For X-Men fans, this is a true holy grail. While its FMVs don't compare with the likes of X-Men #1 or Giant-Size X-Men #1, X-Men #94 is just as important as either of those comics. No, there are no first appearances here. Instead, it's the first issue in writer Chris Claremont's legendary X-Men run. Combined with several all-star artists like John Byrne, Dave Cockrum, Mark Silvestri, and Jim Lee, Claremont took the X-Men from near-cancellation to super stardom. In fact, the title had been reduced to reprints and was on the chopping block before GSX #1 reinvigorated the team with popular new characters. After that, Claremont took over writing duties with X-Men #94, and suddenly the series was blazing hot. By the 1990s, the X-Men became the premiere team in all of Marvel Comics, overshadowing the iconic Avengers and Fantastic Four.

What is catapulting X-Men #94 to the top of the sales charts is the Claremont-heavy X-Men '97. Although the show doesn't exclusively stick to '80s and '90s X-Men comic stories, the majority of what has made it to the screen can be traced back to those classic Claremont tales. That is leading collectors to search out that tantalizing comic book history.

30 DAYS

18. SILVER SURFER #1 (+49)

If it wasn't for X-Men '97, there's little doubt that the Silver Surfer would be the hottest name on the secondary market. After Marvel Studios announced that the Sentinel of the Spaceways would be featured in The Fantastic Four, all those Surfer keys got an immediate boost. Once we learned that Norrin Radd would not be the MCU SS, Silver Surfer #1 overtook even FF #48 as the big seller.

Besides being the first self-titled Silver Surfer series (enjoy that alliteration), the significance here is that Shalla-Bal made her first appearance in this comic. As we now know, she will be the Surfer in the FF movie. Whether or not we will see Norrin remains to be seen. At any rate, Shall-Bal will have plenty of screentime and could be due for bigger things by the time all is said and done. It's enough to have collectors and investors charging to eBay for copies of their own.

60 DAYS

42. THE LAST RONIN #1 (+58)

The Teenage Mutant Ninja Turtles seem to get reborn for every generation. Whether it was the black-and-white days of Mirage, the zany antics of the original cartoon series, the numerous movies and shows throughout the 1990s and into the 2000s, all the way up to Seth Rogen's Mutant Mayhem, the TMNT brand remains as popular as ever. Soon, mainstream audiences will get something like never before.

Weeks ago, news broke that The Last Ronin is getting adapted into a live-action movie. Even better news for fans, the story and violence won't be watered down for a family-friendly audience as this film will be rated R. Like clockwork, buyers were scouring the auction sites for those copies of The Last Ronin #1, which were not hard to find in near-mint grades.

No doubt, this will be the most action-packed TMNT movie ever made. Whether or not the mainstream crowd will accept a mature Turtles flick is questionable, but Ronin fans will be anxiously awaiting the first trailer for this one. Don't forget there's still a game in the works, so this comic has plenty of reason to stay among the Hottest Comics for months on end.

90 DAYS

37. X-MEN #130 (+52)

Maybe it wasn't Taylor Swift, but viewers got a quick glimpse of the dazzling one a couple weeks ago. There she was, looking fresh out of the 1980s among the numerous mutants partying on Genosha in X-Men '97. It didn't appear that she was one of the casualties of the Wild Sentinel attack, so it's likely she'll return in a future episode. Who knows? Maybe she'll join the team and become a resident of the X Mansion.

While the X-Men '97 cameo definitely helps sales, Swift is the reason for X-Men #130's dominance over the past three months. Rumors are rampant that she will suit up as Dazzler in Deadpool & Wolverine, though it may only be for a glance. Still, between the cartoon appearance and the probable chance Swift will play the character in the upcoming movie, Dazzler's time in the spotlight has come. Cue the Swifties' unified squealing.

180 DAYS

25. UNCANNY X-MEN #221 (+45)

Rounding out the Hottest Comics this week is a common addition to the rankings: UXM #221. Not only is there speculation that Mister Sinister will be the main antagonist when the X-Men get their MCU movie, but he's been established as a major threat to the team on X-Men '97. It's good reason to stockpile his first appearances.

Sinister has long been a popular villain in the X-Men universe. In recent years, he's become the resident mad scientist with a comedic flare. However, the version in X-Men '97 seems to lean more into his scarier villain persona. So far, fans are pleased with what they're seeing, and that is translating into major sales for UXM #221. Once he's cast for the MCU, the sales will see an even bigger spike.