Enjoyed the game, but I was able to guess the answers for "rotate" and "assimilation" rather easily even though in the game it told me I'd have a bad time trying to. To me, the answers were very "typical" of what an ego maniacal serial killer would say. All these comments saying Rotate was difficult has me wondering if I was lucky or just that damn good :)
"Riddle Me This" had me rattled. I tried everything that made perfect sense and everything that only kind of made sense. I ended up having to look at a walkthrough, and I found out the answer was one of my first guesses, but I didn't put a certain "determiner" word before it. In the future, I'd suggest having multiple "answers" with different variations for a riddle like that to avoid people going down the wrong track because they thought they were wrong.
As well, I wish it was a little longer as well, yes, solving the riddles can add up in time, but I feel a nice even 10 would have been nice to wrack my brain around.