Emma and Xion were both surprised to realize that the person in front of them had multiple powers. Xion had suspected that Emma was an aeromancer who could control the air and fly up to the 100th floor where he was now.
That's why he did not expect Emma to also have another power, such as the ability to control fire. Mages that could control more than one element were extremely rare. He and Therius were exceptions, and they had never met other multiple-element mages in person.
Was Princess Emma Stardust also a multiple-element mage like them?
Emma was as surprised as Xion. She knew from her mother that multiple-element mage was rare, so she thought Xion was a telemancer because she could not read his mind.