Armor of Unicron
From MediaWiki

Megatron has always sought power at every turn, and this is one of the most striking examples of success. After escaping from the collapsing Energon Sun created to contain Unicron's spark, he had stolen most of what remained of the Chaos-Bringer's power, and his body had been rebuilt with salvaged pieces of the destroyer's armor.[1]
Fiction
Ask Vector Prime
After a mighty battle that pitted the Autobots against the Decepticons and Unicron, Megatron sought more power and searched for the remnants of the disembodied Unicron's spark. From this "lost spark", Megatron forged new armor, being reborn in a new body. Ask Vector Prime
Cybertron cartoon
Notes

- The Armor of Unicron was invented for the Cybertron dub and did not exist in Galaxy Force; since Galaxy Force was not originally in the same continuity as Legends of the Microns and Super Link, there was no need to explain how Megatron was able to survive after plunging himself into the energon sun.
- Regardless of how/when the "Armor of Unicron" concept was brought into the fiction, it was conceptually part of the toy design for Megatron. In robot mode, Megatron's design is partially based upon Armada Unicron's design, with very similar shoulders and arms.


