The 13 Primes versus Unicron
The clash between Unicron above the planet Cybertron and the original 13 Primes created by Primus. Primus chosen defenders and first-born children versus his brother who was dedicated to the eradication of all existence.
Unicron unfurled into a giant robot while the 13 Primes met him on their individual custom designed warships.
Space just outside of Unicron's reach after he had unfurled into a giant robot form.
The entire battle was a hectic mess due to Unicron suddenly appearing in the sky forcing the bots to scramble to engage before he got closer to Cybertron and even then at the battle start he was almost in striking range.
Unicron was offline and physically banished outside of living space.
Long term his banishment allowed Primus's power to echo throughout the physical universe and start countless worlds teeming with all the various forms of life no known.
Unicron managed to get a single clawed strike against Cybertron leaving great trenches on the formerly smooth planet one point he managed to plunge a claw deep enough to cause Primus to scream out in pain, today it is still called The Wound .
Solus Prime created many artifacts and had many backup plans in case one of them fell in battle. Such as creating items that emulated her fellow primes Primus granted gifts. And creating a spaceship with her personality for each of the 13 that was tooled to function for a time as an armor for the primes so they could utilize their gifts on a larger scale.
Unicron was banished and the Primes barely alive the fight destroying all but one of their ships requiring the remaining one days to collect the other primes due to the debris.
Literal being of destruction created by a god-like being to entertain him by destroying everything is opposite twin created.
There were 13 independent minds working together, Solus Prime designed weapons, armors and vehicles solely for the purpose of defeating Unicron.
At the end of the battle, Unicron was forced into a coma-like sleep and banished to the end of reality being pulled by both his home reality and the ones beyond hopefully forever.
All but one of their spaceships were destroyed and all but two of the primes were permanently wounded.
Destroy Primus and all life to earn his creators favor.
Defeat Unicron bringing peace to the universe.