Freedom For Knowledge.

The Emperor replied smugly, "It is not my fault that you chose to assume that I couldn't speak. I don't have to prove anything to you."

Then the emperor asked him, "Would it have changed anything if I could talk?"

Ragnarok didn't say anything to that. He would still have killed everyone and he still planning to eat this one too. He likes silent food but he is not one to shy away from the work needed to make his food silent. 

The Emperor chuckled at his silence. "You're an Executioner. You're all the same. You're all stupid and selfish. You only care about yourself and not others. I knew right from the moment that you entered the cavern that you would take advantage of the situation. Your hunger for power makes you so predictable. Trying to convince you not to eat them would have been a waste of time and energy."