Cinder, despite being the least experienced with Maiden powers in comparison to Raven and Raven having the upper hand at almost everything, manages to beat Raven to near death because she's Cinder. However, Raven harikiris herself before Cinder could claim her prize. Yang suddenly gets a burst of Maiden powers mid-fight and ends up beating Mercury with ease. Ruby confronts Emerald and struggles. She's afraid.
"What are you doing!? Finish her!" Jaune protests. She never really put any thought into what'd happen if she were to actually have the villains at her mercy. And when Jaune said finish her, that's when Ruby has a panic attack and drops her scythe. She breaks down into tears and cries about Penny. Emerald begins to understand that her actions had severe consequences and that, had Ruby had the balls, she'd be dead by now.
Ruby refuses to kill, not out of some 'holier than thou' or naive bullshit, but because she's still a kid and even though her innocence is shattered thanks in part to Emerald, the thought of actually ending someone's life is just horrible to her. Jaune decides to stop healing Weiss and pick up his sword. "Fine, I'll do it myself." Jaune approached Emerald, but Ren grabs Jaune's shoulder and asks him "is this really what you want to be?" Jaune presents his reason as to why he should kill Emerald, bringing up how they're in this mess because of not only her, but her subordinates as well. He then gives out a vow that he will never forgive them for what they did and that they'll soon meet his blade. That's when Ruby shouts "ENOUGH!"
Everyone looks at Ruby.
"No more... No more killing... Please." She's on the verge of tears. Jaune hesitates. Despite talking a big game about killing them, he too is afraid of actually doing it. Even when he says how killing them would be no different than how they'd kill Grimm, he chokes. The two begin to cry. Oscar looks at them and Ozpin laments, "they're just kids." All while Hazel just stands there next to him, as though sharing what may be the only mutual agreement they'll ever have.
And then Lionheart grabs Oscar and runs off with him to his office where he offers him to Salem in trade for being free. Salem, however, is pissed with Lionheart. One job. He had one job. Let Cinder take the Relic and go while the White Fang blow up Haven. Now the plan's on the kibosh thanks to the Spring Maiden trading hands, especially after Qrow warns Yang to run away from Cinder. Leo tries to explain that Oscar is Ozpin, but Salem refuses to have any of it and uses her Seer's tentacle to choke Leo. Oscar decides to run off despite Ozpin's protests, mirroring how Ozpin possessed Oscar despite his protests during his fight with Hazel.
We then see a shadow of Leo slowly dying as more tentacles come for him. Rewarded as a traitor deserves.
Yang runs out where she soon finds Adam. He smirked, brandishing his blade. Cut to black and cue irritated fans everywhere.
Next episode has Ruby and Weiss run to face Adam as well. They have a brief chat as Adam brings up how he's the new White Fang leader now. Weiss says that the faction will pay for what they did to her life, Ruby swears revenge for what happened to Yang and Yang is just angry at him for what he did to Blake. Adam smirks and tells them that they'll be reunited with Blake soon, as soon as he is done forcing her to watch him murder each and every one of them.
"That's where you're wrong!" Blake calls out as a sudden army of Faunus run in and fight the White Fang. Blake explains how he failed assassinating her family and that the White Fang will be in her custody now. Adam gets legit angry and readies his blade. At the same time, Oscar reunites with JNR and find Cinder emerge from the basement, pissed as all hell and demanding to know where the Spring Maiden is. Jaune just tells her that she'll never lay a hand on any maiden and strikes a pose along with the rest of them. Hazel takes this time to grab Emerald and Mercury (whose legs are completely FUBAR'd) and gets out of dodge.
Soon, it plays This Will Be The Day as RWBY is reunited fighting Adam while JNPR is reformed, fighting Cinder. It's the best fight of the entire volume as each side gets their focus. We also have Sun and Ilia take on Banesaw. The fights end up turning into a curbstomp battle, finally for the good guys for once, as they effectively beat up Cinder and Adam.
Adam's fight ends with Blake impaling him in the gut and Yang Spring Maiden punching Adam in the head, breaking his mask and revealing he's not a Faunus at all. He goes into a rant about how he despises humans for how they treat the Faunus because of some sob story about how he lost a Faunus friend or parent. Blake tries to reason with him, telling him it's never too late to turn things around, but Adam retorts. Now it's his turn to Keikaku the shit out of his failure. He had a few Faunus secretly record footage of Lionheart being exposed as a traitor and run off to show to as many people as possible while Adam held them off. When Blake asked why he would ever want to do that, as the knowledge of a Faunus headmaster being in league with a terrorist organization would set relations back to before the Faunus Rights Revolution, he just retorts that he wants to just spite everyone, human and Faunus alike. He doesn't care about what he's fighting for. He just wants everyone to tear each other apart and show that, at the end of the day, they're all just animals.
Unfortunately, the White Fang overhear this and begin to turn against Adam. Blake decides to make this change in leadership official by stabbing Adam in the gut and taking his detonator away. This just scars Ruby some more and she's too scared to talk to Blake, even when everyone else congratulates her.
On JNPR's end, they beat up Cinder. Ren chops off her Grimm arm and makes a comment on how it's reminding him of the Nuck's arm, Nora breaks Cinder's legs and Jaune gouges out Cinder's remaining eye. The result being that she's reduced to a flailing, screaming banshee. Jaune just stands over her as Oscar asks if he's going to do it. If he's going to finish her. Jaune just smirks and says, "No. I like her like this." And he puts away his sword. RWBY return and Jaune notices how they're reunited. There's a moment of bait and switch where we think Jaune's upset that RWBY is back together but JNPR will never get that chance, but he smiles and starts to induct Oscar into JNPR. Ozpin, however, refuses. He needs to stick close to the shadows since Salem would want him, especially given what happened with his fight with Hazel. Qrow then informs the others to check the basement.
There, they see Raven's body. Vernal is still bleeding out, so Jaune uses his Semblance to heal her and get the information. Vernal explains the whole story and there, Yang begins to forgive her mom and realize just how wrong she was in doubting her. Even Qrow feels a little saddened by this. Ren just says "Hey, if Raven is the Spring Maiden but the Maiden we're told about by Lionheart ran away ten years ago, wouldn't that mean that she-" But Nora shuts him up because how dare he bring up horrific implications for the coolest girl ever. Yang goes to activate the chamber and take the Relic. With the Relic in RWBY's hands, Salem's plans are effectively halted. The first, major win for the heroes.
There's a montage where they chill and celebrate their victory. Vernal even approaches Jaune and asks him for a spot on the team. Jaune accepts, and even is humored at the fact that Vernal's last name or her true name (if you go with the idea that Raven made her change names) starts with a P. Everything is just peachy keen.
Suddenly they realize that Cinder's gone missing. It soon cuts to a Mistral wasteland as we have the villains picking up the pieces. Cinder and Mercury are too crippled to go on and Hazel is just waiting for Grimm escorts to pick them up. However, Cinder's pained expressions end up biting her in the ass as she says how Emerald is a bitch in her presence despite being blinded. This shatters Emerald and decides, in that moment, to run off. Hazel lets her go since he's reflecting on Oscar's words on his sister making a choice, and thus he'll let Emerald make her choice.
It's Hazel's turn to talk about how they need to prepare for the oncoming war now that Ozpin has delivered the first crippling blow in this entire war as we have a montage of RWBY being happy (save for the obvious hint of Ruby being afraid of Blake), JNPR finally being reformed, Qrow and Oscar walking away from Haven, no longer feeling the need to help the group any longer, Ilia and Sun celebrating with the White Fang, ditching the masks and bringing back the old symbol, and Raven being buried with honor. Then Hazel says some odd wording about how the Great War will begin. Grimm come to pick up Hazel, Mercury, and Cinder as, suddenly, airships begin to bombard Mistral and Haven. RWBY goes out to see what the hell is going on as Weiss noticed the Airships. She frowns and realizes who's instigating the attack.
Cut to Ironwood sitting in his iron throne with an even larger five o'clock shadow. Hazel's monologue shifts to Ironwood as it's revealed he's the one to say it. He turns his chair and announces his new weapon. It's a pod, and in the pod, a pair of familiar green eyes light up.
Smash cut to black. Roll credits.
Stinger: Mercury gets some good R&R as his entire half is replaced with Centuar legs. Hazel is working out. We then see Tyrian sniveling before Salem as she says how much of an utter failure he is and that only his death can sate her. He tries to do so in front of her, but she corrects him and says how he is to die in battle. He complies and with his new cybernetic tail, he goes off. Cinder, on the other hand, is still, silent. Salem is saddened by this, just briefly. As though to confirm Ruby's hypothesis, she kills Cinder, draining her powers and inheriting the Fall Maiden for herself. She then sneers and says how she'll settle matters herself.