The Kokubourou's Declaration of War

The Kokubourou's Declaration of War (黒芒楼の宣戦布告, Kokubōrō no Sensenfukoku) is the 28th episode of the Kekkaishi anime adapted by Sunrise.

Summary
Yoshimori is asleep at home when one of his mother's bird Shikigami arrives with a message, warning him that enemies are approaching and that he should cooperate with Masamori. Shigemori agrees, stating that they may soon need the Shadow Organization's help. Yoshimori suggests working with the Yukimuras, but Shigemori stubbornly refuses, telling him that a 400 year rivalry isn't so easily settled. Aihi presents several improved human disguises to Byaku, who tells her to use it on some subordinates. This reminds her of the loss of Hisui, which she is still upset about. Aihi applies the new disguises to four Ayakashi, but Kaguro chooses the older Q-Type because it should be more challenging to fight with in it. On the school roof, Yoshimori wonders why the feud between his family and the Yukimuras is so important to the older generation. He is happy that Tokine doesn't see him as an enemy, though he admits that they used to be much closer when they were younger. His happy memories are interrupted when Gen joins him.

Kaguro and his group make their way to Karasumori Academy in broad daylight, amazed by all the things they usually miss (since Ayakashi typically can't handle sunlight). They take over the school's broadcast room, and Kaguro announces them as being from Kokuboro, which alarms the Kekkaishi and Gen. Kaguro claims he wants to negotiate at the usual place. Yoshimori and Gen try to stop Kaguro's group from leaving the school, but Tokine stops them, so that the other students don't get involved. Gen disagrees with this, since he knows the Ayakashi will only be stronger at night. Yoshimori, Tokine, and Gen discuss the Ayakashi after school lets out. Tokine is concerned that they never sensed the Ayakashi until the announcement started. She wants to ask Tokiko for advice, but Yoshimori wants them to handle it alone, since Tokiko and Shigemori would only fight each other.

Yoshimori rushes to Karasumori Academy that night, updating Madarao to the situation as they go. They join up with Tokine, Hakubi, and Gen at the school's gate, and then confront the Ayakashi group, only to find Kaguro has borrowed chairs and tables from the school to make the meeting more pleasant. Kaguro's group is introduced as Haizen, Haroku, Sekia, and Sanan, then order the Kekkaishi to hand over Karasumori without a fight. Sensing Kaguro is the strongest, Gen rushes him, but is taken down with one hit. Kaguro then destroys Madarao and Hakubi, leaving only Yoshimori and Tokine able to fight. The Ayakashi grab Gen and run, knowing Yoshimori will chase them, and lead he and Tokine into an area marked off with stones that cancel out Kekkaishi powers. Tokine tries to draw their attention so that Yoshimori can escape, but instead he stays to protect her. Next, they use Yoshimori's plan: him giving Tokine a boost so that she can leap over the Ayakashi and land outside of the barrier.