Kekkaishi - Season 1 Episode 43 Second Advent of the Black Clouds

Yoshimori leads the trio, Sen and his friends, into a forest where he engages a friendly battle with them. Yoshimori easily overpowers Sen's two friends, but Sen manages to sneak right behind Yoshimori. However, at that moment a purple aura surrounds Yoshimori causing Sen to back away. Toshimori plays shougi with Masamori. Masamori finds Yoshimori in his special training ground and informs him that Kaguro is not someone he can deal with and that his goal should be to protect Karasumori. Meanwhile, Sakon prepares for an assault on Karasumori.