Cor's solemn look is mixed with a little sympathy for a brief moment. He knows that it's one of the worst case scenarios for the entire royal line, losing the Crystal. And yet...

There's the undertone of a growl in Cor's voice. "Power, as far as we can tell. Either the Emperor wants to use the power himself, or he wants it as a power symbol of its claim in the entire world." He closes his eyes for a moment, and then opened them back up, continuing in a more confident tone. "There's still a very good chance of us getting it back, though, and we've already made much progress along those lines."