Kagura Karatachi is a shinobi of Kirigakure who works ad aid for Chojuro, the 6th Mizukage; during the series, for some reasons, Kagura became one of the new Seven Swordsmen Of The Hidden Mist and I think that he is also supposed to become the 7th Mizukage after Chojuro, since the 6th thinks that Kagura is an incredibly powerful and skilled guy and also he trusts him a lot.
In his first appearance, the first thing that a lot of us notice about Kagura is that he is very similar to the 4th Mizukage; in fact, they have a similar body structure, the same eyes and a similar sign on their cheeks. Then, going on with the story, this theory has been confirmed, since Kagura himself stated that he is really related to the 4th Mizukage, in particular he was Kagura’s grandfather.
In addition, we know that Yagura Karatachi, the 4th Mizukage, is remembered in particular for his bloody and despotic reign that contributed to making Kirigakure a place known as the “Bloody Mist”; moreover, he was a very powerful shinobi and he was also the jinchuriki of Isobu, the Three-Tails Beast. Furthermore, talking about Isobu, as far as we know, it is now free in theory, because Yagura is dead and we haven’t seen already any new seal on anybody from the end of the 4th Great Shinobi War.
At this point comes my theory: I’m strongly convinced that, in the future, more precisely when there will be a war or an important fight, Kagura will fight as an ally alongside with Boruto and his friend and in that moment we will see how powerful he will have become; in particular, I think that he is going to become the next jinchuriki of the Three-Tails Beast, since he’s supposed to own Yagura’s skills and, for this reason, he should be able to bear the seal.
Another thing I thought about is that Kagura has always defined himself as a “monster” because, as we saw in his flashbacks, he has a violent ability when using a sword to fight and he’s not able to control that ability; for this reason, there’s also the possibility that he has already received the seal of Isobu, he hasn’t already shown it to us and that could be the reason why he’s the owner of such an incredible strength but he can’t control it. In fact, if you think about it, also Naruto hasn’t been able to control Kurama for several years.
Anyway, despite which theory is going to be confirmed, I believe that Kagura is an amazing character with an interesting personality and awesome skill and, for this reason, he will become one of the strongest Seven Swordsmen ever.