Cryokinesis

Cryokinesis was the ability to create and manipulate ice, snow, and wind. Boreas, god of the North Wind, and his daughter Khione both have this power, and since Zethes and Calais are demigod sons of Boreas, it's possible that they would have this power as well. It can be presumed that any child of the two gods listed above would have cryokinesis (although there are none mentioned.)

Powers
No demigods have had cryokinesis in the series; however, the general extent of this power is:


 * The ability to summon and control snow, ice, hail, sleet, frost, and possibly wind at will.
 * The ability to create or summon blizzards
 * Possible ability to fly
 * Likely immunity to freezing and possibly some resistance to burning (or simply more prone to burning since fire and ice are opposites)
 * In The Lost Hero, Khione summons a nuclear blast with cold instead of heat. It's possible that demigods have this power, although she may have been able to do this thanks to her power as a goddess