Andrea has the mutant ability to solidify air and more solid substances. However, the more solid the substance, the harder it is to fully solidify. Andrea's ability lets her create forcefield-like constructs that can stop bullets and block passage. She can focus her ability to create razor-sharp discs capable of cutting through almost anything.
Working in conjunction with her brother Andreas, she can focus his destructive abilities with near-pinpoint accuracy. If they link hands, she and Andreas can generate blasts of destructive energy more powerful than any other mutant can manifest.