You can heat the air in an area. Everything within it will keep getting hotter until stopped. The objects or people in the area will either start to burn or melt. Metal and other meltable materials will melt, while unmeltable objects or organisms will be turned to ashes. The area you can burn things in will increase with practice. Will only affect objects or organisms you want it to affect in that area. If you choose to leave something in that area unaffected they won't even notice the heat.