Expulsion of Unicron

It was a brutal war, it was a bitter war, and most importantly, it was a visually spectacular war. Unforunately... I'm being told this would be very expensive to animate, so instead here's an image of the Thirteen charging into battle... with cool lighting!

Kicking off the beginning of recorded Cybertronian history, the Expulsion of Unicron was the epic battle between the Chaos Bringer and Primus's chosen disciples, the Thirteen. More hellish and grueling than could be imagined, the battle concluded with Unicron's defeat and banishment from Cybertron's region of the universe.

“	Before the beginning... There was Primus. And there was Unicron. One, the incarnation of creation—the other...of destruction. For eons, Primus and Unicron battled, the balance of power shifting between them more times than could be counted. Only by creating the Thirteen—the original Primes who preceded me—was Primus finally able to defeat Unicron and cast him out. Primus became one with the very core of our planet, creating life through the Well of All Sparks, while Unicron was never to be heard from again...until now.	”
—Optimus Prime, "One Shall Rise, Part 1"

Conceptual history

The concept of the Explusion of Unicron has arguably been around since the Marvel Comics series issue "The Primal Scream", which introduced the first of many interpretations of the Primus/Unicron backstory. This original "Theomachy" between Primus and Unicron be acknowledged and expanded on with 3H Productions's "Covenant". A story written by Simon Furman about the titular group, "Covenant" would introduce the idea of Primus creating unique beings who were created to protect the Grand Plan from Unicron. This basic idea would be recycled in Transformers: The Ultimate Guide, which established that Thirteen Primes fought Unicron at the beginning of history. During the 2000s, Aaron Archer would further develop the members of the Thirteen, creating sketches of the Thirteen, Unicron, and Primus.

Transformers: Prime would introduce the first visual depiction of the Thirteen's battle against Unicron with "One Shall Rise, Part 1", albeit in a short flashback sequence narrated by Optimus Prime. Transformers: The Covenant of Primus would provide a much more in-depth prose version of the battle, explaining the Thirteen's tactics and strategies.

Since 2013, no other continuity has explored in-depth the Thirteen's battle against Unicron. The 2005 IDW continuity established uniquely non-mythological origins for Primus, the Thirteen, and Unicron, deliberately avoiding this concept. It did establish a conflict involving Primus and other gods of myth, but this conflict did not involve Unicron or the Thirteen. Subsequent franchises Cyberverse and EarthSpark would explore specific members of the Thirteen without mentioning Unicron, while One would depict the Thirteen as being at war with the Quintessons. The only continuities since The Covenant of Primus to hint at the Thirteen's battle with Unicron are Fun Publications's Another Light, which concluded the story of the multiversal singularity incarnations of the Thirteen, and Power of the Primes. Whether or not Hasbro will depict the Thirteen's battle against Unicron in future Transformers franchises remains to be seen.

Fiction

Aligned continuity family

Before the Expulsion

In the beginning, Primus fought an endless conflict with Unicron, with neither side achieving true victory. With prior attempts to defeat Unicron failing, Primus created the Thirteen, who were imbued with facets of Primus and Unicron's natures and abilities, which would allow for new strategies to combat the Chaos Bringer. Immediately following their creation, the Thirteen split into three groups:

• Warriors:
  • Prima
  • Vector Prime
  • Megatronus
  • Onyx Prime
  • Amalgamous Prime
• Strategists:
  • Alpha Trion
  • Quintus Prime
  • Liege Maximo
  • Micronus Prime

• Free Agents
  • Alchemist Prime
  • Solus Prime
  • Nexus Prime
  • The Thirteenth Prime.

The Primes divided themselves long before encountering their common foe, with the earliest conflict emerging between the Primus-like Prima and the Unicron-like Megatronus. Yet their common goal of defeating Unicron, along with Thirteen's comforting words of "All Are One", kept them united. They trained together, practicing exercises and attack maneuvers, developing relationships with each other over time. As they looked for new ways to face Unicron, Megatronus requested Solus create the Requiem Blaster. While hesitant at first, Solus decided to trust Megatronus, a decision that would mark the beginning of a deeply intimate and loving relationship between the two Primes.

The Thirteen's Battle Against Unicron

Aftermath

With Unicron's defeat, the Thirteen Primes ruled over Cybertron during the Age of Primes. Although they had survived, many of the Primes had severe physical and mental wounds. Time would heal the physical wounds, but the darkness of Unicron began to feed off of their differences, which would slowly develop throughout the Age of Primes, resulting in the War of the Primes. The Covenant of Primus Over time, matter gravitated toward Unicron's fallen form, eventually forming a planet which found an orbit around a distant star. One Shall Rise, Part 1 The Dark Energon that oozed from Unicron's body would be collected and stored in Trypticon Station. Exodus

During the Great War, Megatron achieved what Unicron did not by contaminating the core with Dark Energon, forcing the planet to shut down and reboot. Exodus Several stellar cycles later, the gravitational pull of a planetary alignment caused Dark Energon to erupt from the Earth, One Shall Fall and re-awakened Unicron from his long slumber. One Shall Rise, Part 1 The reincarnation of Thirteen, Optimus Prime, would lead his team of Autobots in battle against Unicron, eventually teaming up with Megatron to enter Earth's core and unleash the full power of the Matrix of Leadership. One Shall Rise, Part 3 Unicron would return again after Megatron's demise, reanimating the remains of Predacons into undead Terrorcons, who attempted to snuff out Primus on Cybertron. Optimus Prime would once again defeat Unicron, who would be trapped within the vessel that once held the AllSpark. Predacons Rising

Fun Publications

Since time immemorial, the Thirteen, children of Primus, fought Unicron. Prima, leader of the Thirteen, wielded the mighty Star Saber in the Thirteen's conflicts with Unicron. Ask Vector Prime, 18/05/2015 Solus Prime forged the Terminus Blade for herself and her brethren to cross dimensions in their campaign against the primordial entity. Out of the One, Many

Prime Wars Trilogy cartoons

Solus Prime created many tools to help defend against Unicron, including the Enigma of Combination and the Requiem Blaster. After her lover Megatronus used the Blaster to vanquish Unicron, she welcomed him back to her forge. Its purpose now served, Solus believed the weapon should be destroyed to prevent its misuse, though Megatronus believed it was safer in his care. The Swamp

References

	Timeline of the Aligned continuity family
Theomachy (Expulsion of Unicron) Age of Primes (War of the Primes) Age of Evolution (Great Cataclysm) Age of Origins Age of Wrath Golden Age Age of Rust Great War (Great Exodus)