"why the overwhelming desire to conquer the known universe?"

Because I am a god, and it should be mine.

"why take on the personas of gods?"

Kneel before your god! I am your god, and you will acknowledge me!

"other than the sarcophagus, do you sleep?"

I do not have the petty needs and weaknesses you mortals have. I am a god!

"when did you realize you could take hosts?"

It was a time so long ago your feeble human brain could not comprehend it.

"who dresses you people?"

Our lotars. Why do you ask such a meaningless question? Kneel!