Birdbrain

A member of the Monstructor Six, Birdbrain was part of the first know combiner ever know in history(unless you consider Nexus prime one) but was sealed away by the Autobots until she was freed with the rest of her teammates by the Decepticons.

Despite what people say about her Birdbrain isn't dumb at all, her pretender shell gives her great site to see Autobots from 20Km away but this messes with her sensors, to the extent of effecting her in bot mode.

She can combine with his teammates to form Monstructor.

History:

Birdbrain was born some time before the Malignus-Guardian war and stayed neutral with a grope of friends, During the war they found the Matrix of Combination and him and his grope accidently became Monstructor.

As Monstructor she lived in the sea of rust and was eventually captured and locked away by the new Autobots, They were freed by the Decepticons during sentinel times and they joined the Decepticons out of gratitude.

She helped train the other combiners as Monstructor, and during the ensuring battle against the Autobots attacked Victorion along with Devastator, Liokaiser, Abominus and Dinoking before being swatted away by Volcanicus[Operation: Combination]

She was on Floron 2 when space knights were on it and combined into Monstructor[confusion on Floron 2] 

Notes:

She’s based on the G1 Decepticon of the same name

She shares her Bodytype with Brisselback, Gairyu and Rairyu