I'll give you a breakdown of what happened/we learned about each character this episode.
Tengan - Tengan entrusted his hope to Mitarai, using this killing game as a way to force his hand into broadcasting his hope video to the world. Neither he nor Mitarai are aware of the repercussions of doing so. Tengan did not intend for Mitarai to participate in this killing game. To make sure it still continued until Mitarai would be effectively forced to share his video, he made sure that Mitarai's NG code was to make use of his talent, which includes showing people his hope brainwash video.
Mitarai - Mitarai is incredibly resentful of the fact that he has never done anything good for the side of hope and has only contributed to despair. This anger has boiled up inside of him, and now that he has his chance to spread hope. He wants to ensure that no one can stop him, and that he gets his moment to shine. To accomplish this, he broadcasts this brainwash hope video to all the soldiers entering the site of the killing game and to Asahina in order to prevent Naegi and Munakata from interfering. He truly believes that what he is doing is right though, being completely unaware of the fact that brainwashing to bring hope is just as malevolent as brainwashing for despair.
Asahina - Home girl got the short end of the stick once again. Got brainwashed by Mitarai to restrain Naegi until she was brought to her senses. Not even a few minutes later she gets shot in the leg and begs Naegi to go stop Mitarai while she's left bleeding.
Munakata - My dude saved Naegi and Asahina before they were almost killed, and goes on to create a diversion to stop the soldiers from getting to Naegi and Asahina.
Naegi - Dude's gotta do what Naegi does best, be our protagonist. He's trying his best to get to Mitarai to talk some sense into him and stop him from what he's doing. Gets cornered by soldiers.
Hagakure - Yes, you heard me. He did something. He dove in front of Naegi without any shots being fired and immediately surrendered, and created a diversion for...
Togami - Mr. Affluence appears with his secret service dudes and smacks the shit out of the soldiers attacking Naegi.
Chisa - Girl is chilling in the afterlife theater watching this all go down. She's in her normal mindset here, and tells Junko after her speech that hope is just about to begin.
Junko - Shows up to explain how Chisa lead Munakata down this radical path to eliminate despair and was responsible for the divide between Tengan and Munakata as a result. She also summarizes Tengan's reasoning for starting the killing game.
Komaru and Toko and Monaca - girls got brainwashed from Mitarai's broadcast
Hajizuru - My dude killed a bunch of people and we saw his silhouette!!!!!!!!!!!!!!!!!
Juzo - unintentionally fucked it all up by disabling the wristbands whoops