On Atmos, the brave Sky Knights are locked in combat against the Cyclonian Empire under the leadership of Master Cyclonis. Leading the fight are the Storm Hawks, a group of young Sky Knights eager to prove themselves as heroes. One day at a Cyclonian outpost deep in Cyclonian territory, the construction of a mysterious device is underway. As the device was nearing completion, Master Cyclonis and her chief enforcer Dark Ace arrive at the outpost to personally oversee it. They were greeted by the head Cyclonian scientist.

Head Cyclonian Scientist: You grace us with your presence, Master Cyclonis!

Master Cyclonis: How goes the construction of the weapon?

Head Cyclonian Scientist: We are nearing completion. It will be a matter of days until the weapon is fully armed and operational.

Master Cyclonis: Has the weapon been properly tested?

Head Cyclonian Scientist: Not yet, Master Cyclonis. The...the Crystals we used to power the weapon is...volatile in it's current state.

As the scientist said this, Master Cyclonis appeared displeased.

Master Cyclonis: How disappointing.

Head Cyclonian Scientist: I...I can assure you that the men are working as fast as they can to complete the weapon.

Dark Ace: Master Cyclonis is in no mood for excuses. You promised Master Cyclonis a weapon and it has yet to be provided.

Head Cyclonian Scientist: As I said, the weapon is nearing completion. Once it's completed, the weapon will be the pride of the Cyclonian Empire.

Master Cyclonis: Let us hope this weapon is as you promised. The consequences of failing me will be....dire.

With that, the Cyclonian scientists doubled their efforts to finish the construction of the weapon. After days of construction, the weapon was finally completed. It was a similar design to the Storm Engine. Inside the weapon was a core powered by a various array of Crystals. Master Cyclonis and Dark Ace personally oversee to the weapon's testing. Meanwhile in the world of Remnant at the Evernight Castle, Cinder Fall had been summoned to Salem's Throne Room. Inside the Throne Room, Salem was tinkering with a Seer. When Cinder approached the Throne, she bowed before Salem.

Cinder: You summoned me, my master?

Salem: There is a great disturbance, Cinder. At first it was such a quiet thing. I did not notice it. But now I wonder if it has always been there, I merely did not sense it before. The sound built so slowly, but when you listen for it, you can out out the strains, even over the background life of this world.

Cinder: What do you mean? 

Salem: Since time immemorial, there have always been stories of....other worlds beyond the fabric of our own. Many have dismissed it as mere fantasy, even myself at one point. Now I am convinced that unlocking those secrets could prove invaluable to our grand plan for Remnant. All we need is to seek it out....

Salem then uses her magic to try and pinpoint and harness the disturbance. At the same time in Atmos, Master Cyclonis orders the activation of the machine. Across the two worlds, a strange power began to build up in both the machine and the Seer. As the power began to build up, a black dome of energy began to surround both the machine and the Seer. What followed was a powerful but contained explosion. In the lab, the Cyclonian scientists were about to order an evacuation, but Master Cyclonis stops them. In front of them was what appeared to be a cosmic doorway where the machine was. After a moment of silence, Salem and Cinder walk through the doorway.

Salem: Interesting....

Salem and Cinder soon found themselves surrounded by Talons. Cinder prepared to unleash her Maiden powers on them, but Salem gestures Cinder to stand down. 

Master Cyclonis: It seems we have an uninvited guest. Who are you? 

Salem: I am Salem, Queen of Darkness. And who might you be?

Master Cyclonis: I am Master Cyclonis, Empress of the Cyclonian Empire. 

Salem: So the stories are true, other worlds exist outside of Remnant. How....interesting. 

Master Cyclonis became curious about Salem. She could sense a great power within the Grimm Queen. It didn't take long for Cyclonis to put the pieces together.

Master Cyclonis: So the machine somehow opened a gateway between our worlds. 

Salem: Your machine had help with my magic. Now you strike me as someone with....a great vison. 

Master Cyclonis: And what if I am?

Salem: In pursuit of a new world....no cost is too great.

As Salem proposed an alliance with Master Cyclonis, the young Empress took a moment to consider it. Master Cyclonis knew that Salem would betray her the first chance she got. But the power Salem wielded could prove instrumental in her war against the Sky Knights. After careful consideration, Master Cyclonis approached Salem. 

Master Cyclonis: Very well, Salem. You have piqued my interest. You will have your alliance. 

Salem: A wise decision, Master Cyclonis. I am very much looking forward to working with someone as....illustrious and powerful as yourself. 

Salem smiled as she and Master Cyclonis shook hands. Dark Ace and Cinder glanced over to each other, suspicious of each other. Despite this, they would respect the wishes of their masters. Master Cyclonis and Salem would soon tell each other about the nature of their worlds as well as the Heroes who stand against them. In that moment, a deadly alliance was formed between the Cyclonian Empire and Salem's Faction. What no one realized that his deadly alliance would set off a chain reaction which could potentially beak the fabric of not only Atmos and Remnant, but the Multiverse as well.