WARNING: The following contains spoilers for Boruto: Naruto Next Generations Episode 164, "The Forbidden Jutsu of Death," now streaming on Crunchyroll.
For some time, Boruto fans have debated whether or not Sasuke has actually taken over as the successor to Kakashi. In Naruto, Kakashi wasn't as disconnected as an older Sasuke with his students, but he did have some sour ways, such as bad communication and dripping snide remarks at times that were couched in comedy towards Naruto. Now, the anime has revealed his successor isn't Sasuke at all. It's actually one of Konoha's new seniors: the eccentric Mugino.
Kakashi is known for unusual yet genius tactics in battle, and Mugino showed that recently by having Boruto jump in a drain so perfume on him couldn't be used as a tracker. Boruto got annoyed with him in that mission, an escape from the Land of Silence after being framed for Queen Sakuya's murder, and it reminded us a lot of when Naruto would scream in frustration with Kakashi.
It becomes clear just how much Mugino is Kakashi 2.0 when they encounter the other Haze ninja, Yūga, as he stalls for his siblings to escape with the Hashirama Cell. Yūga turns into a Pikachu-like golem that can absorb chakra from Boruto's Team 7, leaving them at their wit's end. Not even Boruto or Konohamaru can devise a means of attack as the beast is impervious to almost anything.
Mugino quickly susses out the way he drains his victims and uses himself as bait in a selfless and lone-wolf manner that feels like a tribute to Kakashi. When the creature tries draining Mugino, the shinobi flips the script and locks him in a hold, exposing his weak spot -- a red gem -- for his allies to attack. Boruto and Konohamau duly oblige, dropping some Rasengan bombs to destroy the golem. Boruto thinks Mugino died, but he's alive and well. On the ground, he tells the kid he needs to listen and become a better ninja as he has a lot of work to do. Mugino doesn't care to mince words, and Boruto retorts with venom as well, calling Mugino a sketchy leader and someone who sucks at communication and being a team player.
It's highly reminiscent of Naruto's first mission with Kakashi against Zabuza and Haku. Ultimately, the Konoha ninjas got the job done. It was clear they'd have to refine their relationship to be proper partners, and we get the same impression with Boruto and Mugino, who respect but don't really like each other yet. The banter's there, as well as the tough love, so one has to think they'll get there soon enough, as Konohamaru, Sarada and Mitsuki can testify that both ninjas are an acquired taste.