When the official website for the series announced back in early February that Black Clover would end with episode 170, the inevitable conclusion was that the series would have to pull a stunt akin to the main Inuyasha series, where it would just end (because of catching up to the source manga) rather than going out at the conclusion of a major storyline. That is, more or less, what ends up happening here. However, anime producers have apparently learned a few things from the intense fan blowback over the cavalier handling of Inuyasha's end, so the story at least finds a reasonable stopping point: it brings Asta's story full circle and shows everyone engaged in preparations for the next big step the story will take. The only question is when that big step will be in anime form.
Asta's attempt to complete the Devil-Binding Ritual plays out the way that only Asta could pull off: by coming to terms with the devil within him rather than enforcing his will upon it. This episode formally reveals within the episode content that the devil's name is Liebe and that he was the lowest of the low in the underworld because he (like Asta) had no magic. However, that is also precisely what allowed him to pass through the seal without being summoned by a human. The woman who appeared at the end of last episode (and at the end of the opener), whom we now know was Licita, accepted him and effectively adopted him. From what is shown in Liebe's flashback, we can assume she did so partly because Liebe was the one person whom she could safely be around due to the side effects of her magic and partly because Liebe was a replacement for the baby boy that she had to give up because (presumably) she could not safely be around him. And in the most casually-presented bombshell revelation of the whole series, that baby is heavily implied to be Asta. In other words, Licita is Asta's birth mother.
Even before that drop, I wondered if there might be a connection, as Licita's hair is the same shade of gray as Asta's and they both have the same kind of energy. The reason she did so makes complete sense, but it also means that it was entirely coincidence that Asta and Yuno were found outside the church in Hague Village at the same time. This setting has never really recognized gods or religion, but that still seems like too huge a coincidence for some greater power to not be meddling. However, this contributes to the explanation for why the five-leaf clover grimoire ended up with Asta: because there was an established affinity. Both Asta and Liebe had no magic, both are the sons of Licita, and Licita is responsible for Liebe being in the five-leaf grimoire. No “because he's the protagonist” gimmick is necessary here; with the missing piece of the five-leaf grimoire's backstory now known, that it would fall to Asta was to be expected. The one still-missing piece here is how, exactly, Liebe developed anti-magic while within the grimoire, but I can let that one slide.
This, of course, means that Liebe and Asta have every reason to work together. Asta can sense that Liebe's heart really isn't into taking over Asta, and that they have very synchronous goals. Nacht and his devils may think it's foolish and stupid to for Asta to forge a pact of equals with Liebe, but it is the best-case scenario for them. Most importantly, it fits with the prevailing theme of the entire franchise: as powerful as you may get individually, you achieve the best results through teamwork. Look back at all of Asta's major victories, and you will see that hardly any of them have resulted from a purely solo effort; in fact, he's usually been stymied when he has tried to do things alone. Now he has a true partner with him at all times.
All of this is coupled with some sharp action sequences, too, as Asta draws upon inspiration from all of the people that he has fought with and against over the course of the series. That gives a sense of cumulative impact to this ending that Inuyasha distinctly lacked. Seeing Noelle assume a more take-charge attitude at the end is also a plus and a sign of how much she has grown, and it was only fitting that other major players also got their brief moments at the end. In all, it makes for a remarkably strong finale, even if it is ending in the middle of a major story arc.
So what's next for the franchise? A movie – the first for the franchise! - has been announced already, but this franchise is popular enough that an sequence seems likely once the manga get far enough ahead again. Hence I would expect a “Black Clover Shippuden” (or something like that) maybe sometime later next year. For now, though, that's a wrap.