The mutant Gas Girl, Tal Nahii, is a member of the 30th Century superhero team known as the Heroes of Lallor. The bizarre origin of Tal Nahii who was born with the mutant power to turn into any form of gas at room temperature, thanks to her parents being irradiated during an Atomic accident earlier in their life. The young girl exhibited the ability to transform into any gaseous element at room temperature. Taking great joy at her unique disposition she is known as a bit of a show-off and enjoys shocking people with her sudden transformations. A native of the planet Lallor, she found others born with abilities like herself also due to an Atomic accident on Lallor.