Nightbird (G1)
Nightbird was a robotic ninja warrior created by the "famous scientist" Doctor Fujiyama, ostensibly to show how advanced Human technology had become. The Decepticons stole Nightbird, and Bombshell implanted her with an enhanced brain chip which turned the drone-like Nightbird into a true ass-kicking machine. Nightbird broke into the Ark and stole the Autobots' World Energy Chip, which contained the locations of a variety of energy sources, energy sources that the Decepticons would most assuredly use for conquest!
The Autobots later beat the crap out of Nightbird and took her back to Doctor Fujiyama, who locked her up until 2025 or so, at which point the retard built an entire army of the damn things. Then they killed Daniel Witwicky and Wheelie. Presumably they all blew up or died or something after that. I don't fucking care, honestly.
In the Dreamwave comics, she was the star of the movie Enter the Nightbird.

