When Captain Marvel finally arrives to save the day in Avengers: Endgame, it won’t be the first time we see Marvel’s newest hero. Captain Marvel was first teased last year in the post-credits scene after Infinity War, and the superhero’s origin movie is set to premiere some six weeks before Avengers 4 hits theaters. But Endgame might introduce a brand new Marvel hero that we’ve never seen in any of the previous films, and now there’s more proof to support it.

A few weeks ago, Jeremy Conrad said on Twitter that Marvel could bring the Black Knight to the MCU, saying that the hero will be introduced with the help of the Quantum Realm. Now, thanks to all the official revelations that followed the premiere of Ant-Man and the Wasp, and especially the DVD and Blu-ray release, we know that the Realm is more critical to the MCU than we thought. We learned it’s not a place devoid of life because intelligent creatures do populate it, including heroes — the best proof is that Jane Van Dyne spent the better part of her life in there.

Since then, we also received plenty of confirmations that the Avengers will travel to the Quantum Realm in Endgame, wearing the same kind of suit that Hank Pym needed to go to the Realm and retrieve his wife. Conrad is now back with a more detailed MCU Cosmic report that offers more evidence that Black Knight will be in the upcoming Avengers 4 movie.

He explains that Marvel releases “True Believer” comic reprints around the time of a movie release, which are “$1 one-shot comics from a major storyline or event that has some sort of connection to whatever movie is out at the time.” That way, people unfamiliar with the characters can catch up with the comics in time for the movie.

Marvel has reportedly planned “True Believer” reprints for Endgame, including “standard” ones like Ronin and Thanos & Gamora, according to the MCU Cosmic founder. But there’s also one that fans didn’t necessarily see coming:

Marvel is issuing a reprint of the first issue of The Gatherers Saga. This is a short event that began in Avengers #343 in 1991 where the basic concept was that Avengers from alternate timelines are brought together, and Black Knight is involved.

Dane Whitman/Black Knight might be one of the characters populating the Quantum Realm city in the image above — that screenshot, by the way, comes from Ant-Man and the Wasp, which quietly teased the complexity of the Realm ahead of Endgame.

When we first talked about the possibility of Marvel bringing Black Knight to the MCU, we noted that Hiroyuki Sanada’s role for Endgame isn’t yet known. The actor, who played in The Wolverine, and who will reportedly star in John Wick 3 later this year, will appear in Avengers 4. But to this day, his character hasn’t been revealed.

Endgame premieres on April 26th, which means we have plenty of time to learn what Sanada’s role is, and to get more details about Black Knight’s apparition.