Because you have slated (though I wonder if you understand that this project requires you to be comfortable with being on camera) unlike the rest of the dismissed submissions, I will at least give you performance feedback.
A slate tells me a lot about the person, which is one of the reasons why I require them(and to see if people can read and follow instructions like a professional). Your slate shows me a lack of confidence because its low volume and dearth of energy.
The laugh is forced instead of maniacal like that of a dark God who thinks everyone else is inferior. To the Grand Master, he thinks it's absolutely hilarious that someone has the gall to come and challenge him. So Grand Master can't help, but taunt and mock this fool to come and bow down before him.
Narcissistic individuals who suddenly have their lives on the line will absolutely plead and panic for their lives when something goes wrong. That would be a strong choice for that final line.
Voice acting is a lot more than "just trying to sound good." That's amateur work and typical of most of the people here. At it's core, it is still acting. You need a thorough understanding of the character's purpose, objective, relationship, action, etc. You need to feel the same emotions as the character you're performing. It is what makes your performance authentic versus someone who just imitates.
