Fans call three early-2000s series the Unicron Trilogy: Armada (2002), Energon (2004) and Cybertron (2005). They were made jointly by American and Japanese partners, and all three are linked by the threat of Unicron.
Armada
A story about the Mini-Cons — small Transformers hunted by both factions. Unicron appears at the end, and Autobots and Decepticons are forced to unite.
Energon
Ten years after Armada, Transformers and humans build a peaceful network of Energon towers, but Unicron's remains threaten everyone again. The series is known for mixing 2D and 3D animation.
Cybertron
The final part is about finding four Cyber Planet Keys and saving the universe from a black hole left behind by Unicron. In Japan it aired as a standalone series, so in the Western version its link to the earlier parts is somewhat forced.
Is it worth watching
The trilogy is a good pick for those who grew up with it or want to see how the franchise searched for itself between the classics and the modern era. Start with Armada — it's the most cohesive.
