The archmage shifted his attention to Luke. "You wish to know why the princess is important? Simply because she has the most control over the crystal. In fact, she's the last person alive with the knowledge necessary to control the crystal. Furthermore, it was never my intention to have her killed, but we needed it to seem like her life was in danger so that she would flee the kingdom for her own safety, to better facilitate my own rise to the throne.  As for how I can control the army, that is something you don't need to know," he said in a cold voice.  "My ultimate goal? I want full control over the crystal, with no threats to oppose me. Now if you are quite finished, you should leave, before I lose my temper. I have important preparations to make."