Eira stumbled as the ground quaked underneath, however she managed to turn her stumble into a roll. And then the giant threw another rock at her. As it exploded, pieces of shrapnel went by her. Though she didn't get hurt because the ones that came towards her disintegrated into sand. Scowling, she watched as the dragon tried to fling sand onto her flames. They weren't normal flames though, and the sand just fell right on through them. 

Walking to the outer edge of the cloud of flame, Eira stayed just inside its black expanse. She, snarling, walked out of the flames. Only a few wisps covered her shoulders arms and legs as she walked forward towards the dragon. The rest of cloud fell flat against the floor, threatening to cover the ground of the entire arena. Just a few spaces at the edge was clear of the flame's touch. 

THen, like a river, the thin layer of flame surged around the dragon, who was standing on clear ground. Hopefully, the -200 degrees celsius temp. would make his movements sluggish.