Nightmare Knights Issue 4

My Little Pony: Nightmare Knights #4 is the fourth issue of IDW Publishing's My Little Pony: Nightmare Knights comic miniseries. In the issue, Princess Luna's team of former villains attempt to break free of Princess Eris' nightmare magic.
==Summary==
Princess Eris traps Capper and Stygian in simultaneous nightmare illusions—in which Capper helplessly witnesses the destruction of Klugetown by the Storm King's forces, and Stygian relives the moment when Star Swirl the Bearded and the other Pillars of Old Equestria renounced him for stealing their artifacts. In these nightmares, Eris appears before Capper and Stygian like a heavenly angel and offers to save them from their torment if they reveal the rest of their allies' identities and what their plans are.
Stygian sees through Eris' deception and attacks, so Eris traps him in his nightmare forever. However, when Eris offers Capper a life of luxury in return for his cooperation, Capper accepts. Meanwhile, in the casino interrogation room, Daybreaker continues to watch over Tempest Shadow as she relives her own nightmare over and over. Unsatisfied with her duties as the casino's head of security, she attempts to break Tempest out of her nightmare and coerce answers out of her herself. However, the collar around Daybreaker's neck that Eris uses to control her detects her disobeying orders and shocks her with electricity.
Princess Luna finally reaches the top floor of Eris' casino, where she spies Capper betraying his friends and selling them out to Eris. Eris and Capper head downstairs to subdue Trixie, leaving Stygian behind. Once they are gone, Luna sneaks in and uses her natural dream-walking ability to enter Stygian's nightmare in an attempt to free him from it. Back in the interrogation room, Daybreaker has successfully released Tempest from her nightmare. The electric shock from her collar frees her from Eris' control and restores her free will, but she has no memory of her former life as Princess Celestia.
Daybreaker explains to Tempest—at the same time that Eris explains to Capper—how this world came to be in its current state. When this world's Pony of Shadows rose to power centuries ago, the Pillars of Equestria appeared to stop him and seal him away. However, in order to keep chaos running rampant, Eris stole Star Swirl's book of spells. Without it, the Pillars could not complete their sealing spell, and Star Swirl perished while the other Pillars escaped with Celestia and Luna. As the Pony of Shadows' power spread, he read Star Swirl's research notes and became obsessed with turning Celestia and Luna into his agents of evil, even seeking them out in alternate worlds. When Eris refused to help the Pony of Shadows in his quest, he imprisoned her and forcibly used her chaos magic to find the princesses.
After he found them, he began training them as Daybreaker and Nightmare Moon to be his successors, which is the earliest memory of Daybreaker's life she can recall. When Nightmare Moon rose up against her master, Daybreaker—the stronger and more heavily influenced of the two—eliminated her and became the Pony of Shadows' sole successor. In order to further his own power, the Pony of Shadows made Eris create a collar that would limit Daybreaker's magic and force her to obey her master's every word. However, the collar she created made Daybreaker recognize Eris as her master instead. Daybreaker released Eris from captivity, they defeated the Pony of Shadows together, and Eris rebuilt the world in her own chaotic image.
On one of the casino's lower floors, Eris and Capper find Trixie still waging battle against the Great and Powerful Twily. Just as Trixie emerges victorious, Eris knocks her unconscious and captures her. Eris and Capper bring Trixie to the interrogation room, where Daybreaker pretends to still be under Eris' control and Tempest pretends to still be trapped in a nightmare. Eris leaves Trixie under Daybreaker's watch while she and Capper leave to find Luna. Once they have left, Tempest asks Daybreaker to help her find Luna before Eris and Capper do. Daybreaker is nervous about defying Eris' orders, but Tempest reminds her of her original identity and says she is more powerful than Eris.
Back in Stygian's nightmare, he is overwhelmed by guilt from the events that led to him becoming the Pony of Shadows, and Luna is unable to save him without her magic. Remembering that this is Stygian's nightmare, Luna realizes Stygian can only save himself. She reminds Stygian that he himself is the Pony of Shadows and can choose not to be. This helps Stygian break the nightmare's hold over him, and he and Luna finally wake up. Upon awakening, they find Daybreaker, Tempest Shadow, and Trixie standing over them.
==Quotes==
:Tempest Shadow: Open up your eyes! There's no way out of here.
:Princess Eris: Capper?
:Capper: Who are you?
:Princess Eris: Me? I'm a princess. I'm here to save you.
:Stygian: I won't betray my friends! It doesn't matter what you do to me!
:Princess Eris: Oh no, magic. That's right—I'm not really here. And this is your dream.
:Princess Eris: You wanna go back to losing everything you love, or you wanna help me out and live a life of luxury?
:Capper: Tell me more about this life of luxury.
:Daybreaker: I've never had to get a pony out of a nightmare before, but it shouldn't be that hard. I have a sun on my rump, after all.
:Princess Eris: A clever cat like you could have a great life in a world of chance like this.
:Capper: You know what? Usually I'm the type to try and eat the canary, but I like the cut of your jib.
:Tempest Shadow: The Celestia in our world wakes ponies all the time.
:Daybreaker: Who's Celestia?
:Tempest Shadow: You're kidding, right?
:Trixie: I... ha ha ha... I... I did it. I beat Twilight Sparkle. I... I did it! Capper! Did you see that? I out-magicked Twilight Sparkle! Me! I really am the Great and Powerful—
:Tempest Shadow: Luna was her real name, before you were stolen by the Pony of Shadows.
:Daybreaker: Her real name? What's my real name?
:Tempest Shadow: Your name is Princess Celestia. You don't just control fire—you raise the sun.
:Daybreaker: Celestia? My name is Celestia?
:Stygian: Luna, it's no use. You can't save me from him.
:Princess Luna: That's just it, Stygian—there is no him. There's only you!
:Stygian: What?
:Princess Luna: You chose to become the Pony of Shadows because you felt weak and alone. But you're not that pony anymore. You can choose not to be. I can't fight this battle for you. Because the battle is inside you.
:Daybreaker: Hello, sister. We need to talk.