One of the three characters from the "original" world, Prototype is fairly cynical, and aloof. He's not the best at handling anything emotional, despite still being tamed. When explaining the truth of the world to Niko, he ends up making them very upset unintentionally, even stating he wishes Rue were there to do a better job than him.

I imagine Prototype has a slightly quiet, and low voice, that doesn't have quite as much emotion as the rest of the characters. Though, there is still a hint of it.

A robotic effect is optional, but if you do want to include it, please provide a take without it!