Gravis almost couldn't believe that Morus was throwing his life away to get revenge on him. Was he really willing to sacrifice his life for a mere moment at revenge!? That was stupid!
Yet, in this heated moment, Gravis hadn't realized that he had done the same thing as Morus in the past. When Gravis had decided to temper his Spirit with Destruction Lightning, he had also been willing to throw his life away for revenge. He had done the same thing.
Gravis had three choices in front of him now.
First choice: Find and kill a level two Emperor to become an Emperor himself.
Second choice: Trust that his children were powerful enough to, at least, stall Morus.
Third choice: Ask Orthar or Meadow for help.
All three of these choices were terrible. If Gravis found and consumed a level two Emperor, he would need several minutes to finish his evolution. During that time, he was also very vulnerable.