This is how Unicron's return and Autobots and Equines vs Unicron goes in Transformers Prime: Friendship is Magic: Beast Hunters: Predacons Rising.
Smokescreen: "Lord Smokescreen" emperor of destruction.
Bulkhead: How can you sit there? That's some bad mojo.
Bumblebee: What do you know? Knock Out actually shot straight for once.
Arcee: What'd you have to do buff his finish?
Bumblebee: Close. Let's download the data and get out of here.
Bulkhead: Hey. Something's heading our way.
Bumblebee: Movin' too fast.
Unicron: Minions of the Prime, prepare to be obliterated!
Smokescreen: You skewered buckethead with a giant saber and managed to miss his Spark?
Arcee: How are you still alive?
Bulkhead: And where'd you score the upgrade?
Unicron: Megatron cannot answer you at this moment, though I can inform you with utmost authority that he owes his new lease on life to me Unicron! And I will not be so easy to deliver into oblivion.
Megatron: Bothersome pest. That pest is the very one who robbed me of my Spark. And now I possess the power to return the favor!
Unicron: You possess nothing! It is I who possess all that you were and ever will be.
Arcee: We need to retreat.
Bulkhead: The only way out is down. We can't call for a groundbridge until we put some space between Unicron and us!
Unicron: Behold my infinite might!
Smokescreen: Let's roll. Come on, chief.
Arcee: We're out of time.
Bulkhead: Whoa! Stop!
Smokescreen: A smelting pit?
Arcee: Cybertron's been dormant for thousands of years, but that's still burning?
Bumblebee: Ratchet, we need a ground bridge.
Unicron: Servant of Prime, you will now join your brethren!
Bumblebee: You got that right!
Megatron: I... am...weak!
Unicron: But our merciless attack drove the Autobots into submission! They fled for their very Sparks! A victory over unworthy opponents, especially one that did not result in their demise,is far from an achievement. Clearly, our improved state is not enough to accomplish the deed for which I have come. For that, I shall require a much greater instrument of destruction.
Bulkhead: How is this happening? I mean, we put out a call inviting refugees back to Cybertron, and Unicron's the first in line? Not to mention those Predacons. What have we come home to?
Smokescreen: What are we supposed to call him, huh Megacron? Unitron?
Arcee: Really? That's your biggest issue right now?
Smokescreen: Right, right. All right, good. So, what's the game plan?
Bumblebee: While Unicron may now inhabit a mortal form, he is still a god and thus cannot be defeated by customary means. Optimus? Wheeljack! This is Bumblebee. We have an urgent situation.
Optimus Prime: Bumblebee, this is Optimus Prime. Proceed.
Bumblebee: Optimus! Can you hear me? Come in, please. Wheeljack, do you read?
Wheeljack: That hit we took did some damage. Receiver's operational, but we can't transmit. Nothing.
Rainbow Dash: You have your voice back. Now is not the time to go radio-silent. Optimus, in the event that you can hear us, Unicron has found his way back to Cybertron. Repeat the Chaos-bringer is here, on our soil, in possession of Megatron's body.
Optimus Prime: Wheeljack, ensure that the light-speed drive is still fully operational.
Applejack: So, what now I mean, besides hoping that Optimus got the message?
Bumblebee: We figure out why Unicron's here. And what he wants. The big "U" could have taken Equestria behind our backs.
Wheeljack: Why come back to Cybertron?
Optimus Prime: There would be only one reason, Wheeljack. To destroy the Spark of his archenemy Primus.
Twilight Sparkle: But that's the core of our planet!
Arcee: It isn't fair. How many more times do we have to save a world have to fight for the survival of our home?
Ratchet: Regrettably, the struggle between creation and destruction is an eternal one. And the battle lines which separate the two... run through the very Spark of Cybertron. Good and evil. Order and chaos. One victorious, one vanquished, each forming the core of their own separate worlds Cybertron... and Equestria. And now.. The darkness has followed us. All the way home.
Predaking: Hmm. Tracks. The Autobots, the train, and the ponies spoke the truth. Other Predacons do exist.. though it seems they took flight here. Locating my new brethren will be a futile endeavor, unless I allow them to locate me.
Ratchet: Vitals are improving. You will be back on your struts in good time.
Bumblebee: Exactly how long is good time? Because with Optimus missing in action, we could really use Ultra Magnus' counsel. Bumblebee, we have each been witness to those among us who have risen above their station time and again rappers, scouts, even field medics. The Chaos-bringer is at our doorstep, and now, more than ever before, we cannot afford to wait for salvation. We'll launch an attack on Darkmount, provided Unicron's still there. Or first attempt to locate him, in the event he is not.