The Blade was a mistake for the MCU when Marvel tied him into Black Knight’s origin story in Eternals. “Sure you’re ready for that, Mr. Whitman?” was Blade’s response to Kit Harington as he was about to take up the Ebony Blade in the movie’s second post-credit scene. Blade’s presence in the MCU is a bad omen for Black Knight’s future in the MCU, even if it’s exciting for Blade fans.
Pre-Eternals release, one of the most pressing questions about Dane Whitman’s transformation into Black Knight was what steps Marvel would take to do so. Dane acquired the Ebony Blade linked to his uncle and ancestral lineage in the post-credits scene to answer this question.
The door is now wide open for Dane to become the Black Knight in a future MCU film, given that he has the sword now. Where Marvel plans to take him next remains a mystery. Eternals 2, Blade, Avengers 5, or a solo Black Knight movie or TV show on Disney+ are all possibilities for his return in the future.
It doesn’t seem like the best way to approach Kit Harington’s MCU character from what Marvel suggests with Blade’s Eternals post-credit cameo. In the first place, it suggests that Blade is Dane’s next destination. The MCU’s vampires could benefit from having an ally like Black Knight in Blade’s story. On the other hand, Dane would be overshadowed by Blade if he were to assume such a role.
There should not be a Black Knight origin story in another character’s movie. Marvel, of course, would devote most of the story to developing Blade, and Dane would be cast as a supporting cast member. In Blade’s movie, he’s unlikely to be treated as an equal to the Daywalker.
Additionally, this scene gives the impression that Blade will serve as a mentor to Kit Harington’s Black Knight character. A warning about the Ebony Blade from Blade indicates that he is aware of the MCU’s supernatural elements. Dane may be taken under his wing to learn the ins and outs of the sword and its powers from him.
With Blade’s status as an expert swordsman, there is a sense that Marvel will choose him to teach Dane how to wield a blade. If Blade becomes the master and Dane the student, Black Knight’s reputation as Marvel’s greatest swordsman will greatly diminish. The Black Knight is known for being the best in this area in the comics, and it should be the same in the MCU.
Marvel should have kept Black Knight and Blade on separate paths in Eternals rather than tying them together right away (at least temporarily). After both characters had established themselves as MCU superheroes, teaming them up was unnecessary. Breaking away from Blade as soon as possible is the best way Marvel can ensure that Black Knight stands on his own.