Unlike most mutants, Cass was born into a wealthy family of former heroes. Her parents fought crime in Paragon City in the sixties and seventies under the mantles of Lady Thunder and Ice Storm. When Cass was born, both retired from hero work to focus on their new family and to raise their baby girl.
At six years of age, Cassie's powers started to manifest, allowing her to supercool the liquid in the air, turning it to ice and to control the furry of a storm. Her parents taught the young girl how to harness and control her abilities until she was fifteen.
At fifteen she was sent to a boarding school to help fine-tune her abilities, both mentally and physically, and at nineteen was accepted into Harvard as a full time student. Cass' schooling was cut short at twenty-one, however, when the Rikti invaded earth and sent the entire planet into a state of emergency.
The young woman was unable to make it back to Paragon City until after the Rikti were repelled but decided to stay and help rebuild the city.
Cassandra Storm, Ice/Storm Controller
Velocity Gal, Gravity/Kin
Scarlet Seraph, Fire/Rad
Maiden Amazing, Mind/FF
Freedom Belle, Invul/Super Strength
Artemis Val'Ane, BS/Regen
Gamma -Girl, Rad/Elect
Cordelia Storm, Storm/Ice
Violet Justice, Energy/Energy
Adara Hexe, Dark/Dark
Cutthroat Cassie, Thugs/Traps