When Tsubaki learns that the phantom blade Masamune could become a Kishin, she decides to go stop him personally. She and Black*Star thus arrive at the village being targeted, and Tsubaki theorizes that the phantom blade is after souls with fear. Black*Star accuses everyone he meets of being the phantom blade, but it’s not until one of the village boys recognizes the star tattoo on Black*Star’s arm that everyone becomes hostile to them. The villagers know the star as a symbol of the Clan of the Star, and they think that Black*Star is after money, so they run him and Tsubaki out of town. Afterwards, when Black*Star sees that Tsubaki is worried about what just happened, he decides to explain what the fuss is about. It seems that the Clan of the Star had been a family of assassins that would do anything for money until they had their souls taken 13 years ago. At the time, Black*Star had just been a baby, so he had been taken in by Shibusen and doesn’t carry a grudge. Tsubaki is still worried because she hasn’t told Black*Star about her own connection to their current situation, but he doesn’t pry her for that information and is ready to listen whenever she feels ready to tell him.
Meanwhile, back at Shibusen, Stein explains to Maka and Kid that a phantom blade is different from a demon sword in that the phantom blade isn’t connected to a witch. It can take advantage of a person’s fear to possess that person’s soul and takes over their body. Consuming souls leads to the phantom blade turning into a Kishin. At this very moment, Masamune approaches one of the village boys who had been worrying about Black*Star the Clan of the Star. He offers the boy power to combat that fear, and shortly thereafter, Black*Star hears a scream from the village. He arrives just in time to save one of the village elders from the possessed boy, and as the fight begins, Tsubaki explains that a phantom blade cannot manipulate two soul wavelengths. Thus, if Black*Star can cast his soul wavelength into the possessed boy’s soul, then they can free the boy from Masamune’s control. Though Black*Star is fine with doing this, Tsubaki worries that she’s using him, but he doesn’t care and says that she can rely on him even more. Black*Star then begins fighting in earnest, however Masamune responds by striking him with the shadow of the boy he’s possessing. This puts Black*Star in a 2-vs.-1 battle, and so he decides to use his Speed Star ability.
The super speed works all the way until Black*Star slips on the wet ground and slides crotch-first into the monument in the center of the village. He manages to pick himself back up before the shadow can skewer him, but Masamune then prepares a special attack that shoots the shadow at his opponent. Though Black*Star is able to avoid the main strike, he’s caught off guard by the shadow’s ability to sprout spikes to stab him with. He takes a few more hits from the shadow as he proceeds to set up a trap that involves initiating a resonance of souls and catching the Masamune in the Shield Star that he’s able to create afterwards. This allows him to jump up and hit the possessed boy directly with his hands, and the surge of soul wavelength frees the boy from the sword. Tsubaki is quick to catch the sword in mid-air, and she then enters the blade to fight it directly. On the outside, it looks like she’s been possessed, but on the inside, she finds herself in a bleak world. Nearby is Masamune, or as Tsubaki refers to him, her older brother.
I would say they did a decent job keeping the whole Masamune-is-Tsubaki’s-brother thing a secret until the end, but the prologue to the episode with that flashback more or less gave it away, especially when combined with how Tsubaki was so determined to stop him. Still, this was overall a good episode with a fairly interesting fight and a cliffhanger conclusion. It also showed again that Black*Star can be pretty funny even in serious times. There was some of Black*Star’s background too, and though it wasn’t much, it seems like prime source material for more character development later.
In any case, we’ve seen the Black*Star can handle Masamune, but it remains to be seen if Tsubaki can. She is theoretically at a disadvantage because she’ll be without Black*Star, and she doesn’t have whatever special powers being a phantom blade grants. The preview for next week seems to support the idea that she’ll get smacked around in the fight, and that makes me wonder what happens if she loses. Does Black*Star have to fight a possessed Tsubaki? Such a situation would be avoided if she wins, but it’s interesting to consider anyway.