This is how Dark Unicron Rises in The Birth of Thomlight Sparkle.
[Later that night, a large robot with blue stripes down his body and looks simular to Unicron sneaks into the library. He passes the sleeping Thomlight and Nyx on the way and reaches Twilight's room. The robot peaks in and sees Twilight. He sneaks over and grabs her and replaces her with a fake. He tries to sneak off with her but trips over Nyx's tail]
Unknown robot: [grunts]
Nyx: [wakes up] Thomlight? Did you hear that?
Thomlight: [wakes up] Hear what, Nyx? [turns to the doorway and sees Twilight in the robot's arms] Mom! He's got Mom!
Nyx: [gasps] You're right!
[they both fall out of bed as the robot gets up and runs off with Twilight]
Thomlight: Stop! Come back! THEIF!
[the other foals and the Maximals wake up upon hearing him]
Thomlight: He's got our mom!
Other foals and Maximals: [gasp]
[The robot races through a coridoor, still carrying Twilight. Thomlight gallops after him before teleporting in front of him]
[However, the robot leaps over him leaving a trail of blue light. With Thomlight distracted, the robot escapes. But it isn't long before Thomlight, Nyx, the other foals, and the Maximals are hot on his tail again]
Nyx: Stop him! Don't let him get out!
[Thomlight and Nyx chase the robot who picks up speed. The pair do the same and tackle the robot. They tumble into a room where the robot drop Twilight and she falls through an open Space Bridge, whilst still asleep. Thomlight, Nyx, the other foals and the Maximals gasp]
Thomlight: What did you do with our mother?!
Dark Unicron: Sorry it had to be this way. [walks over to the Space Bridge] Her highness' son. [jumps into the Space bridge and disappears]
Snowdrop: Who was that?
Nyx: Snowdrop, I have no idea.
[the next morning]
Optimus Primal: Dark Unicron, a powerful being much like Unicron. Only he is more powerful.
Thomlight: Define: "More powerful."
Nyx: "More powerful" basically means that Dark Unicron is stronger than Unicron.
Thomlight: Oh. Okay.
Skyla: What do you suppose he'll do to Auntie Twilight?
Optimus Primal: I don't know, Skyla. But what I do know is that he was created by an evil robot mastermind named Cylas.
Ari: [gasp] Cylas. I know. One time I was out getting Cyber Matter for Percy when he got injured and then Cylas attacked us.
Nyx: What are you talking about, Ari?
Ari: I encounterd him after Percy got injured and when we went to get the Cyber Matter.
Thomlight: Then what happened?
Ari: Well, I can't quite remember what happened next.
Rhinox: Thomlight, Nyx, why don't you and your friends go into another room? Me and the others need to discuss this alone.
Thomlight: [sighs] Okay, Rhinox. [leaves with Nyx and the other foals]
Rhinox: Anyways, Ari, please continue.
Ari: As I was about to hit him with one of my suction cups, Cylas threw me aside and then tossed me into the river.
Optimus Primal: Wow! You must've had a very bad encounter with him.
Ari: Yeah. I did.
[In the other room, the foals are having a conversation]
Thomlight: We need to find out how to get Mom back, guys!
Nyx: I know. But I'm all out of ideas.
Thomlight: Well, then, it looks like we're going to have to rescue Mom ourselves!
Sweetie Belle: WHAT?!
Button Mash: Are you crazy?
Thomlight: Trust me, it's the only way.
Nyx: But the Maximals and Dad will wonder where we are, and get very upset.
Scootaloo: Come on guys, this is our chance to show what we can do!
Thomlight: Look, if we're to rescue our mother, then it's the only way we can save her.
Nyx: Yeah. I suppose you're right.
Apple Bloom: But wer' gonna need to have someone git' some better weapons, our handguns ain't gonna be enough.
Thomlight: That could be a valid point.
Mucker: I might be able to assit you with that.
Thomlight: You can?
Mucker: Sure, follow me.
[Thomlight follows Mucker up to one of the arsenal boxcars of the Miner Trains]
Thomlight: Mucker, that's just a boxcar.
Mucker: Not just any boxcar. [pulls a lever and guns racks deploy]
Mucker: You got that right!
Thomlight: So, which one do you think I should choose?
Mucker: I'm letting you decide.
Thomlight: I can choose which one?
Thomlight: [walks up to one fo the racks and grabs a SIG SG 551 assault rifle]
Mucker: A SIG SG 551 assault rifle, good choice.
Thomlight: Wow! This one looks so cool!
Mucker: Take another. Be my guest.
Thomlight: [grabs an Ithaca 37 shotgun and looks at it] Aren't shotguns like these suppose to have exject doors?
Mucker: Not that one, it's an Ithaca 37. They exject sheels from the bottom, in the same place you load it.
Thomlight: Hmmm. [grabs another Ithaca 37] I got an idea.
[later, Thomlight is carving something]
Scootaloo: What is he doing?
Button Mash: How should I know?
[Then Thomlight begins drilling something together]
Snowdrop: Ugh! Thomlight, what are you doing?
Thomlight: This. [turns around and we see he connected 2 Ithaca 37 shotguns together] I give you, a double barrel pump shotgun! [racks the slide]
Other foals: Whoa!
Mucker: Nice one, Thomlight. Seems like you've been taught well.
Thomlight: Yeah, Mucker. I know. Do you have another mag capable for the rifle I grabbed?
Mucker: I'm not sure. I'll check.
Mucker: [finds another mag for the rifle] Here we are.
Thomlight: Thanks. [takes it]
Apple Bloom: Now what are ya' doin'?
Thomlight: [removes the current mag from his rifle and then he tapes the mags together in a jungle style] There we go.
Button Mash: I get it, you jungle clipped your mags!
Apple Bloom: Jungle-what now?
Button Mash: He taped his mags together so that when the first one runs out, he can just flip it to the full one.
Apple Bloom: Oh.
Scootaloo: Who taught to you how to do this, Thomlight?
Thomlight: Ratchet. You know, the Autobot Medic?
Button Mash: Yeah. He is a pretty good expert in technology.
Thomlight: Yeah. I know. Nyx introduced me to him yesterday.
Nyx: He's not kidding, you know.
Thomlight: He showed me how to jungle clip these things together and even told me about his past whilst doing so.
Sweetie Belle: I see.
Apple Bloom: Ah' can't believe Ratchet made y'all this good.
Thomlight: I did very well and followed his every instruction.
Nyx: It's true, he did.
Thomlight: I'm not kidding!
Button Mash: We didn't say you were.
Thomlight: I know. I was just saying.
Nyx: I think they already know that, Thomlight.
Thomlight: Now, [loads his shotgun] Let's go!
[the other foals grab their weapons and Thomlight puts his in his saddlebags]
Nyx: Thomlight, are you sure that this is a good idea? Because, you know Dad doesn't want anything bad to happen to you.
Thomlight: You know what they always say, Nyx, you mess with one of us, you mess with all of us.
Nyx: Guess we'll have to tell that to Dark Unicron the next time we see him.
Thomlight: Yes. We will.
Nyx: Either way, you're really smart.
Thomlight: Thanks, Nyx.
Button Mash: [cocks his pistols] Let's go!
Snowdrop: He's right. Let's do this!
Mucker: Wait, before you go. Takes these. [throws some shotgun shells to Thomlight]
Thomlight: [catches them] What are these?
Mucker: Fusion shells, they fire the same kind of blast that Megatron's fusion shotgun does. They're great for battling robots. Believe me, I've used those on many Decepticons and Terminators.
[the foals all set off, leaving behind a very happy Mucker]
Mucker: Good luck, guys.
Thomlight: Thanks, Mucker.
Mucker: Be careful whilst you're out there!
Foals: We will.
Nyx: I still don't think this is a good idea, Thomlight.
Thomlight: [sighs] Nyx, look. I know this might be hard for you and you think these ideas aren't good. But you've got to understand that knowing you shouldn't do something makes you want to do it even more.
Scootaloo: I'm with Thomlight, on that one.
Nyx: Yeah. But Dad might get very upset.
Thomlight: Nevermind Dad. We need to save Mom. She's in terrible danger.
Nyx: What about Uncle Shiny? Or Auntie Cadance?
Thomlight: I suppose they'd be worried about us too. But we need to hurry, Mom is in trouble. Who knows what Cylas could do to her.
Snowdrop: But we don't even know what Cylas looks like.
Thomlight: I know. But Knock Out told me that he was very strong and that we might get hurt. But I know he isn't and we won't get hurt.
Skyla: But what if he has enough strength to defeat us.
Thomlight: Mucker said that these Fusion shells are great for destroying robots, so I'll them against Cylas.
Button Mash: When will you use them?
Thomlight: When the time is right.
Button Mash: Oh. So, do you think we should get going?
Thomlight: Yeah. We should.
Babs Seed: Let's get a doin'!
Scootaloo: I'm ready to kick Cylas' big metal flank. [cocks her Desert Eagle]
Apple Bloom: That bad guy won't last in these parts with us catchin' him.
Thomlight: Alright. Let's go.
[they all start to walk out of castle grounds]
Thomlight: I just hope Cylas hasn't set up any traps for us.
Button Mash: Watch out, Cylas. We're coming.
Thomlight: Not to worry Mom, we're on our way!
Apple Bloom: And when we get ther', wer' gonna kick yer' big metal flank, ya' twisted evil robot.
All foals: Yeah!
[they all race for Cylas' place as we fade out of this scene]
Thomlight: [voice echoes] We're coming for you, Mom!
Nyx: [voice echoes] Yeah!