In Beast Wars transformers, she was a Maximal protoform that arrived on earth, but Predacons captured and reformatted her as a Predacon, reprogramed by Tarantulas. Blackarachnia has mechanical and scientific abilities. In the beginning she worked as Tarantulas assistant in all his plans, but she was more ambitious than any Predacon or Maximal, loyal to no one but herself. she masked herself with false loyalty, until the power from a Vok floating island caused her betray everybody, all this to destroy the Maximals and rule the Predacons. When the Maximal Silverbolt appeared, they slowly developed a secret love affair. When she realized that Megatron II's newest plan would result in her death, she joined Silverbolt and the Maximals, and later gains a Transmetal form. Her creator based her design on a Japanse exotic dancer.
"Dark Poison of my heart!" - Silverbolt
Blackarachnia is no longer a Predacon, she survived the Beast Wars.being a more pasive character. Her new body no longer looks like a Blackwidow, it now looks a purple daddy long leg spider.
Transformers: The Animated Series
Blackarachnia is one of the five main Decepticons. She has a different origin than she did in Beast Wars. Her new design is almost the same as her original Beast Wars CGI model.
Blackarachnia is a freak among Decpticons. Some time back she was an Autobot Academy student, then known as the Elita 1 and friends with Optimus Prime and Sentinel Prime. However her teammates left her on a spider-like planet, Archa Seven, forcing her to take on one for an alternate mode, becoming a techno-organic being as a result. She despises this new form, especially on Earth, where her giant spider mode doesn't exactly allow her to "blend". She will do anything to find a cure for her condition and doesn't care hoe she does it, joining the Decepticons to find such a way while getting revenge on the Autobots.
Abilities in the Animated Series
In her mutant technorganic form, she uses her newfound power 'cyber venom' to paralyze her enemies, and combines it with her natural ability to downloadand mimic character traits of other Transformers along with weaponry for a short amount of time with a simple touch.
Due to trademark reasons Blackarachnia's name had to be changed to Airachnid.