[@Yankee] Happy to see your interest. To answer your question, unless you're particularly skilled in negotiation or subterfuge, it's unlikely that an investigation into Satan's disappearance will be totally bloodless. There are likely many parties that are best served if Satan is never found, and they would need to be contended with.

To clarify what I mean by Ultra-Violence, I mostly mean it as an aesthetic of the overall setting and story. The players are likely to be among the infernal elite, and as a result are a cut above the masses of Hell's inhabitants, and humans are basically below their notice. The barest exertion of strength will reduce most foes to bloody chunks, and you may expect to reap death tolls in the thousands, if not millions. It's gratuitous because, like everything in Hell, it is mean to shock, horrify, and numb the senses.

It's worth noting though, that demons are not really evil; they- like angels, as many of them originally were- don't have a concept of right or wrong. Morality is a concept that only applies to Mankind, who imbibed the fruit of forbidden knowledge. Demons do as they will, obeying their whims and fulfilling their own desires as it suits them, and this takes many different forms among their multitudes.

I hope this was enlightening.