Megastorm is the Predacon Duke of Destruction and younger brother to Galvatron, the Emperor of Destruction. He believes in being realistic and conservative when it comes to goals and strategy and hence tends to have a rather different veiwpoint than his more bold and reckless older brother. Finally when Galvatron began his audacious quest for the Angolmois energy the differences between them became too great and Megastorm began to consider how he could seize the reigns of command and stear them back towards sanity. Galvatron is well aware of his younger sibling's attempts at treachery, but looks the otherway purely out of brotherly love.

Megastorm can transform into a tank. He is later upgraded by angolmois into Gigastorm, who is a giant mechanical Hojoni, which gave him a base mode and a battle station mode, along with a Gigascouter drone. His personality was likewise magnified to drive out all compassion, weakness and doubt. The upgrade included an enlarged title of Arch-Duke of Destruction.

(Source: Wikipedia)