Severing the spell that bound her to the Imperator's will and awakening the "Zero Type Izayoi," Tsubaki uses the power of the Murakumo Unit Prototype to follow her own justice and convict all sins. Although she escaped the darkness of the past during which she could only avert her eyes, her sword trembles. In the future lies a "true light" to be obtained.
|Stage 7: Hakumen|
Hakumen: ...I've been expecting you.
Izayoi: L-Lord Hakumen... what are you doing here?
Hakumen: You've unleashed Izayoi...
Izayoi: Thanks to Jin, I was able to break free of the Imperator's curse. It seems I am able to wield Izayoi's power as well.
Hakumen: I see... Then let me ask you, Tsubaki. Why do you seek such strength?
Izayoi: ...Justice. Unconditional, absolute...justice.
Hakumen: And what does "justice" mean to you?
Izayoi: That is...to punish the evil, and...
Hakumen: It would seem doubt still clouds your mind, Tsubaki... Continue on this path, and Izayoi will be nothing more than a burden to you. You will fall victim to its power once more.
Izayoi: Lord Hakumen... then what must I do?
Hakumen: ...Draw your sword.
Hakumen: I shall be the judge of your determination.
Hakumen: Indeed... You are aware of your own justice, yet choose to avert your eyes. Hmph, it is like looking at my self of old.
Izayoi: Lord Hakumen...?
Hakumen: Tsubaki... With these final words, I shall be on my way. Do not be afraid of opening your "eyes."
Izayoi: To...open my eyes...?
Hakumen: My time is up... I shall leave the rest to her. I bid you farewell, Tsubaki. Perhaps next time we cross swords, we can both put our own "justice" to the test.
|Stage 8: Mu-12|
Mu-12: I've been looking for you, Tsubaki.
Mu-12: You know, we're all worried about you, Tsubaki, even Makoto is, so... I-- um... I'm not really sure what to say in a situation like this, but... But...I'm sorry? Can you please come back to us?
Izayoi: *Chuckle* You really haven't changed, have you, Noel. Always apologizing.
Mu-12: O-Oh, I'm...sorry...
Izayoi: There you go again.
Izayoi: ...Noel, you know I was really jealous of you. After graduating from the academy, you got to be close to Jin, and...you had everything that I didn't...
Mu-12: But Tsubaki, I really looked up to you back then...a-and even now. You're so nice to everyone, and you could do just about everything.
Izayoi: It's not that I could do everything... I just tried twice as hard. Though it seems that was a mistake...
Mu-12: You couldn't have made any mistakes, Tsubaki. I was always the one....causing others trouble.
Izayoi: When you do that...it reminds me of a rabbit.
Mu-12: T-Tsubaki, stop saying weird things... I was being serious!
Izayoi: Now...I think it's about time we settled this.
Mu-12: ...Tsubaki, if possible I...don't want to fight you.
Izayoi: Noel, please... I want to see what it is that dwells inside of me, with my own eyes...so I beg you.
Mu-12: You're...serious, aren't you?
Izayoi: Don't hold back.
Mu-12: ...Summoning Lux Sanctus. Murakumo Unit, activate!
Izayoi: ...Thank you, Noel... In my right hand, I wield the sword of judgment, and in my left, the scales of truth. I serve as the judge... to condemn those who have sinned!
Mu-12: Are you ready, Tsubaki!?
Izayoi: Let's go, Noel!
Izayoi: ...Where am...? ...I see, this must be my..."darkness" ...The darkness inside my heart, which I refused to see...
Jin: ...Don't look away, Tsubaki... Don't become... like me.
Izayoi: Huh? Lord Hakumen...? Makoto...Noel......Jin. Even in complete darkness... I can see clearly. *Chuckle* I can't believe it was that easy. How did I not understand this before?
Izayoi: I don't want to lose them... I don't want to feel separated.
Izayoi: Because... I love you all.
In the Colosseum, Tsubaki was led into a trap where she was forced to fight against Noel Vermillion, Makoto Nanaya and Jin Kisaragi. After battling against both Makoto and Noel, Tsubaki sought true strength from her weapon, becoming Izayoi. She was conflicted between the Mind Eater and her own thoughts and love for her friends. Izayoi battled Jin, winning but believing she had killed him, being enough for Mind Eater to be lifted. Tsubaki was free from the curse, but remained in Izayoi's form as she embrace Jin, Makoto, and Noel, and as she was introduced to Homura Amanohokosaka by Kagura Mutsuki.
Tsubaki continued stay as Izayoi while she protected Homura and then as she was sent with Makoto to help secure Kushinada's Lynchpin. Using its power, she defeated Carl Clover and the Deus Machina: Nirvana.
Tsubaki, who awakened the power of the "Zero Type Izayoi (Sixteenth Night)." Following her own justice, she convicts all sins. In order to bring the "World's Evil" Ragna the Bloodedge to justice by her own hands, she searches Kagutsuchi.
Act 1: Phantom of Labyrinth
|Stage 3: Hibiki Kohaku|
Hibiki: I've been looking all over for you, First Lieutenant Tsubaki Yayoi.
Izayoi: Hibik... err, Captain Kohaku.
Hibiki: Your mission was to locate Captain Jin Kisaragi... I do not understand what you were doing here.
Izayoi: ...I am fulfilling my true responsibility.
Hibiki: And what might that be?
Izayoi: To destroy the Grim Reaper...
Hibiki: I do not believe even Lord Kagura would give you such a mission. Please enlighten me as to whose orders you are carrying out?
Hibiki: You really leave me no choice. I will stop you before you commit an act of treason.
Hibiki: K'uh... How can this be... First Lieutenant Yayoi.
Izayoi: I'm sorry, Hibiki...
Izayoi:...? Why does something feel...? No, it is. Something is definitely different. Could "this" be the correct answer? Then... Where are you, Ragna the Bloodedge...?
|Stage 6: Jin Kisaragi|
Jin: Tsubaki...!? Tsubaki, what is that armor...?
Izayoi: Yes, the Zero-type Izayoi keeps me protected. I'm so glad to see you're okay.
Jin: ...Obviously. There is still something I must do.
Izayoi: ...Is that... to kill Ragna the Bloodedge...?
Jin: It is. And then to erase Hades Izanami.
Izayoi: But Jin, you're still not ready to...!
Jin: I'm fine. Noel Vermillion is in this world... which means there's a high chance we're in the right one.
Izayoi: I'm sorry, Jin. But I cannot let you go.
Jin: This is my mission! I will slay anything that stands in my way, even you, Tsubaki.
Jin: K'uh... you've improved, Tsubaki...!
Izayoi: You're in no condition to see that man...
Izayoi: ...I shall inherit your mission.
Jin: Wha...!? W-Wait, Tsubaki!
Izayoi: I will kill Ragna the Bloodedge in your stead, Jin.
|Stage 7: Ragna the Bloodedge|
Izayoi: There you are... Grim Reaper!
Ragna: Hm? Hey is that... the Sealed Armament? Or is it my imagination. Why does it feel so familiar...?
Izayoi: I am from the Fourth Thaumaturgist Squadron of the NOL -- First Lieutenant Tsubaki Yayoi. In the name of justice, I will condemn you, Ragna the Bloodedge!
Ragna: Wha...!? Wait Ragna? Is that supposed to be my name!?
Izayoi: Yes... You've been affected by the Embryo... but...
Ragna: Whoa--!? What the hell are you trying to pull!?
Izayoi: I cannot have you cause any more pain for Jin. So I'm sorry... but I must remove the source of evil from this world. I will defeat you, Ragna!
Ragna: Gaaaaaah! Grah... Dammit...!?
Izayoi: This is the end, Grim Reaper. Do not resist.
Ragna: Shit... I'm not gonna die without figuring out what the hell's going on...!
Izayoi: Cease. Give up hope... Your death has been assured from the moment you were evil. As long as you live, the world cannot find peace. That is why...
Izayoi: ...!? Who are you!?
Nine: Hehe... I'm impressed. You actually sensed my presence...? I've never seen it in person before... Izayoi's true form.
Izayoi: You're... Phantom!?
Nine: I believe this is the first time we've met face-to-face. I am Nine...
Izayoi: Nine of the Six Heroes...
|Stage 8: Nine the Phantom|
Izayoi: Answer me, Nine... What have you done with Ragna the Bloodedge?
Nine: I can't tell you that. I can't let you defeat him right now, either.
Izayoi: ...! As one of the Six Heroes who defeated the Black Beast, surely you're aware of the dangers of letting him roam free.
Nine: I am. But he is still of value for me. I suggest you withdraw from this.
Izayoi: You must be joking.
Nine: Hardly. At the moment, I'm much more interested in you, Tsubaki Yayoi.
Nine: Yes. So first, why don't you show me your caliber?
Nine: Ah, the true Izayoi... Haha, fascinating power.
Izayoi: What is it you want? What do you plan to do with the Imperator in the Embryo?
Nine: What I want...? Well, there is someone I would love for you to slay, with your blade, Izayoi.
Izayoi: Don't make me laugh. Do you honestly think I would obey you?
Nine: Defeat this person and killing Ragna the Bloodedge... Making your wishes come true will be easy.
Izayoi: ...What do you mean?
Nine: It's quite simple... if you really want to defeat Ragna the Bloodedge... Then... Before the Day of Reckoning, the Imperator... No-- Izanami must be defeated. By your hands.
Act 2: Nightmare Memory
|Stage 3: Rachel Alucard|
Izayoi: Ikaruga... Ragna the Bloodedge is somewhere here, too... I need to find him.
Rachel: ...Would you mind waiting just a little longer?
Izayoi: Rachel Alucard...? What do you mean, wait?
Rachel: The circumstances have changed. There is still something Ragna must accomplish. You cannot kill him. Not yet.
Izayoi: ...I fail to understand your logic. You yourself said that his existence was a threat to this world. And now you tell me not to kill him? I cannot accept this. Can you prove that you're not acting irrationally?
Rachel: You hopeless child... Perhaps I'll play with you a little. That may help. I do admire how straight and honest you are.
Izayoi: Why must you go this far? You've become so weak, and you choose to become weaker still to protect Ragna the Bloodedge.
Rachel: ...I've already told you. It is necessary. Surely you understand this world well enough. Our enemy is not Ragna but Izanami right now. ...To succeed, you must find Noel Vermillion.
Rachel: The key to this world is in the hands of your missing friend.
|Stage 6: Hazama|
Hazama: Well, well, well... First Lieutenant Tsubaki Yayoi. What a coincidence. What brings you here...with the Izayoi in hand, no less?
Izayoi: Captain Hazama... I can ask you the same question. Why are you here?
Hazama: Intelligence department stuff. I'm really not at liberty to say.
Izayoi: (Does Captain Hazama have memories of the original world...? Although right now, I do not sense Terumi's presence...)
Hazama: You're alone. ...Your friends won't be joining us today?
Izayoi: ...!? (There's no mistake... He's THAT Hazama...!) Captain Hazama. You will be judged.
Hazama: Owww... Was that absolutely necessary?
Izayoi: There's no point in feigning ignorance. You remember. The old world...and who you are!
Hazama: I suppose I cannot fool the keen eyes of the Izayoi. If you'll excuse me, I just remembered I have something to do.
Izayoi: Wait! There..! What is...this strong presence. There's something towards Ibukido...!
Hazama: That's the last time I listen to your advice... Look at what I've been through... So... Is she any use to us? ...I see. That's good to know.
|Stage 7: Hakumen|
Izayoi: Lord Hakumen!
Hakumen: I've been expecting you... Tsubaki Yayoi.
Izayoi: Expecting me...? Then you've come after this immense power, too...?
Izayoi: What on earth could be causing this? If you know, please tell me.
Hakumen: Before I do, there is something I must confirm.
Izayoi: Confirm... What may that be?
Hakumen: Your disposition.
Izayoi: *pant pant*
Hakumen: ...But of course. Tsubaki, you have a quality of which even you are not aware. That is, besides wielding the Izayoi. Jin Kisaragi is weak and you have begun to inherit his powers.
Izayoi: Jin's power...? You don't mean--!
Hakumen: ...The Power of Order.
Izayoi: This is the strong presence I felt earlier...! Above us?
Hakumen: It has come...
|Stage 8: Izanami|
Izayoi: This is...? We've been teleported. Did you summon me? Imperat... No, Izanami.
Izanami: Indeed I have. I welcome you, Tsubaki Yayoi.
Izayoi: But why? What are you after?
Izanami: Nothing... I felt the Azure only appropriate for you. You may have it, if you wish. With its power, you can transform this world as you desire. All of it. Does that not pique your interest?
Izayoi: Sorry, but I really don't believe you right now. I won't let you forget about our past... Besides, I don't need that. There's something even more important than my own wish...
Izanami: Oh? And what might that be?
Izayoi: I thought it was obvious... your death.
Izayoi: ...! Why...?
Izanami: The weapon that can kill anything... Sadly, it cannot kill death itself. What it can kill, is the being distorting this very world in which we exist.
Izayoi: This world is...being distorted?
Izanami: Yes. Erase this person and your world shall become a reality. You can spend the rest of your days beside your dearly beloved...
Izanami: Hear me, and understand this. This is the truth of our world. The one controlling it, is someone you know...very well.
Izayoi: It can't be... No...!
Izanami: Noel Vermillion. Slay her, and the veil may finally be lifted from before our eyes. You are the only one who can do this. You wield the Izayoi.
Izanami: Now, right this world. You are both judge and executioner. Order can only be restored... by you.
Act 3: The Replacement Blue
|Stage 3: Jin Kisaragi|
Izayoi: I really didn't want to run into you this way, Jin... But I cannot overlook what you're about to do. You might believe this is the right path. The way to save the world... But I don't care. I won't let you kill Noel.
Jin: There's no reason to repeat myself... But I'm not going to simply back down from what I've chosen. I have the Power of Order. If I don't fight to protect this world, then who will? Noel Vermillion is an obstacle, so I will do what must be done.
Izayoi: Jin... You aren't the Order of the entire world... You're a single human being and so is Noel... As Tsubaki... I will protect my friends!
Jin: ...I see your resolve is true. You won't give up until one of us is down, will you?
Izayoi: Absolutely not!
Jin: I'm sorry, but that doesn't work for me. I'll back off from this fight.
Jin: Don't get the wrong idea... I'm only backing off and that doesn't mean the rest of the world will give up on Noel Vermillion, also. The entire world has eyes on her.
Izayoi: I am aware! And even then, I must fight for my friends!
|Stage 6: Makoto Nanaya|
Makoto: Tsubaki! Why are you dressed that way...!?
Izayoi: I cannot be choosy about my methods. Everyone in the world is after Noel... I need this strength to protect her.
Makoto: Are you going to be okay...? Izayoi's power takes away your eyesight, doesn't it...? I'm sure it's still dangerous, even if you have it under control...
Izayoi: I'll be fine. My mind was weak before, but...I won't fall victim to Izayoi or Izanami anymore.
Makoto: Please... You're always pushing yourself too hard. You're so worried about others, you don't see what's happening.
Izayoi Thanks, Makoto. I've made you worry so much, haven't I...?
Makoto: Huh? Wh-What do you mean? That's totally fine... We're friends, right?
Izayoi: Yes, we're friends. Very important ones... So let's protect the one other friend we have.
Makoto: Well, DUH! Say, Tsubaki... What do you say to a little sparring. You know, to get warmed up? That way we'll be ready to take on all those bad guys who want Noel.
Tsubaki: ...You're right, I think that's a great idea. I need to see how strong I've become, as well.
Makoto: I think that should about do it! I feel much better now that I've warmed up. Thanks, Tsubaki.
Izayoi: You've helped me re-focus, as well.
Makoto: Now... Time to go find Noellers!
Izayoi: I hope she's still okay... The whole world's after her right now. It's up to us to save her!
|Stage 7: Noel Vermillion|
Izayoi: Noel! This is where you were... I've searched all over!
Noel: T-Tsubaki...!? And the Zero-Type Izayoi...? No... Not you, too...!? How could you--!?
Izayoi: What's the matter? Oh no... She's becoming unstable. Calm down, Noel... I'm here to...
Noel: No! Stay away! Please... Stop this. I don't want to fight. I don't want to fight you, Tsubaki...! Why is this happening...? What have I done? Why is it a crime for me to be alive!? I don't want to die... I don't want you to kill me...! Does everyone hate me now...? That's so... That's...! I hate this world...!
Izayoi: She's losing control... At this rate, she's going to be consumed by darkness without even knowing... Just like me. Noel, I'm going to bring you back! It's MY turn to save you now...! Zero-Type... Fight with me.
Izayoi: Noel, wake up!
Noel: I... I'm sorry, my head feels really...hazy. I'm not really sure about anything, Tsubaki...
Izayoi: That's alright, it's fine. I'm glad you're back to your old self... Now, let's get you to safety. We need to find Makoto and think about what to do next...
Izayoi: ...! Lord Hakumen...!?
Hakumen: Tsubaki Yayoi... or perhaps I should call you Izayoi now. I shall take you into my custody... and reap Noel Vermillion's life!
|Stage 8: Hakumen|
Izayoi: Lord Hakumen...not you, too. Do you really intend to change the world by taking Noel's life!?
Hakumen: I seek only the destruction of all evil in this world... I shall sacrifice any life necessary, should it stand in my way. Be it kings or gods... I will not hesitate. There is no time to waste -- I will put an end to everything. Now, lend me the power of the Izayoi!
Hakumen: Your will is irrelevant... I am the white void... I am the cold steel... I am the just sword! My flesh and bone exist to eradicate this world of evil! I am HAKUMEN! The end has come!
Izayoi: Even if that is the world you seek, or the calling you must answer... I do not believe it is correct! What you are trying to do is wrong, Lord Hakumen!
Izayoi: "To put an end to everything..." That is what you said earlier. Does that have anything to do with what you said...about your own sins?
Hakumen: ...That is not for you to know.
Izayoi: If it is not necessary, then so be it... But I will be the one to make that decision!
Hakumen: The more you know, the closer to death it will bring you. Those are the sins I now bear... Do you wish to bring about your own destruction!?
Izayoi: K'uh...! Your attacks are quite... strong! But I stand here now because there are things I cannot give up!
Izayoi: ...!? What...? Is this the... Azure? Gathering?
Hakumen: Curse you, Yuuki Terumi...!? Get out of here, Tsubaki! Don't touch the Azure!
Izayoi: Huh--!? What's happening...? It's getting dark...?
Izayoi: Eee...k!? N-No... this isn't... me? I'm looking at someone else's memories... from when I... died? These are...Lord Hakumen's memories? But why am I... Am I dead? Who is that? Why am I...alive right now...? I was supposed to...die? Then, if this memory is yours, Lord Hakumen... ...Who does that make you...!?
Tsubaki only transformed into Izayoi once, to defend the Amaterasu Unit and Jubei from Nu-13 alongside Hakumen. Despite their best efforts, they were nearly defeated until Ragna, Noel, and Jin arrived to help them. 
In the new world created by Ragna, a woman who used to be called Tsubaki Yayoi threatened to kill Rachel. She stopped when she realized the vampire had fallen into the “Hell” called possibility . Datamining has shown that this woman is called Izayoi.
- BlazBlue: Chrono Phantasma Official Site (JP), Izayoi
- BlazBlue: Chrono Phantasma, Story Mode, Chrono Phantasma, Episode 14: Inherited Will
- BlazBlue: Chrono Phantasma, Story Mode, Chrono Phantasma, Episode 17: Doomsday
- BlazBlue: Central Fiction Consumer Edition Official Site (JP), Story - Izayoi
- BlazBlue: Central Fiction, Story Mode, Episode 011, Chapter 092
- BlazBlue: Central Fiction, Story Mode, Episode 012, Chapter 100