Marvel: Thermokinesis

Idie Okonkwo (Oya)
Oya has the ability to alter temperatures around her. However, she cannot simply create heat and cold; she can only rechannel temperature.

Robert Drake (Iceman)
Iceman is a mutant with the superhuman ability to lower his external and internal body temperature, projecting intense coldness from his body. Like any normal human being's, the nerve centers for regulating Iceman's body temperature are found in the part of the brain called the hypothalamus. However, Iceman can mentally override his hypothalamus to allow his body temperature to be lowered by an unknown internal mechanism. This ability converts the latent thermal energies in and around his body into an unknown form of energy that is efficiently dissipated. A related mutation has rendered his body tissues unaffected by sub-zero temperatures. Iceman can consciously and immediately lower his body temperature from its normal 98.6 degrees Fahrenheit to absolute zero and lower within the span of a few tenths of a second. Iceman's power to generate cold is so great, he was able to stop a massive nuclear explosion.

As his body temperature falls, the surrounding moisture in the air that is in contact with him is similarly lowered. Just as condensed moisture forms frost, this moisture forms an icy covering which encompasses his entire body. It also obscures his facial features. When Iceman first began to completely lower his body temperature, this covering took on a more snow-like appearance. But as he learned to increase the severity of his coldness, the covering assumed the consistency of crystalline ice that it has today. This ice constantly cracks with any movement of his body and immediately reforms. Through practice, Iceman has learned to control the intensity of his coldness, and he can selectively lower the temperature of isolated parts of his body.

Roberto da Costa (Sunspot)
Sunspot has the ability to project heat in intense waves when he absorbs and re-channels solar energy from any part of his body to raise the temperature. Sunspot can also absorb heat into his body to lower the temperature in his immediate area. He can also project and absorb heat directly into/from people, causing intense discomfort at their fluctuating body temperatures.