Cordelia Frost is a fictional mutant character in the Marvel Comics Universe. She the younger sister of Emma and Adrienne Frost, as well as being the youngest of the four Frost siblings. She was regarded by her parents as being the "lost" one in the family, and as such she rebelled by dressing in black, having sullen, sulky moods and being argumentative.
At first not much was known about Cordelia's powers other than the fact she and her sisters all have passive psionic powers and that she is immune to Emma's telepathy. This immunity is due to her sibling status, much like Cyclops and Havok. She was revealed later to be an empath. She used her powers for the first time in the form of mind control during Generation X; Here Cordelia was able to create personalities that possess her victims' mind. In this way, she controlled the mutant Mondo. She would often use this to her own advantage and soon discovered that she could implant emotional states into others' minds. This ability could make an enemy think they were blind, or that they were talking to someone else instead of Cordelia. She later received an enhancement of her power in the form of psionic blasts. Though she couldn't control it at first, Cordelia learned to use her psionic blast as an offensive weapon, to render opponents unconscious or to erase memories.
In Generation X, Emma stated that Cordelia is the "Professor X of the empaths" and may be the most powerful empath on the planet, easily able to overpower people with the same gift. However, she has no formal training in using her power and thus her skills are only based on her own experience and skill. Despite her apparent skill, her lack of training comes as a drawback, since Cordelia isn't able to control "strong" mutants. But whereas most empaths, even powerful ones, have a range that is within their immediate vicinity, Cordelia has one that could easily manipulate an entire city without reaching her range limitations.
Mind Control: Cordelia is able to create personalities that possess her victims' mind. In this way she controlled the mutant Mondo.
Empathy: possesses the power to read emotions and project emotions. Though the ability is minor at best.
Through a normal quirk of mutant physiology she is also immune to her sister Emma's telepathy. A concept that is common amongst siblings.
Due to lack of practice Cordelia isn't able to control "strong" mutants.