As for the clues - I think it's still better for the GM to come up with them, Arko is right - they can be taken from HeroesWorld life, but the main thing is that the hints are interesting, not as direct as "mug*sh*t*" What I like in this regard - some rhyming riddles, strange lines that we have to decipher ("chaos shall illuminate your soul, mortal" - maybe something along those lines)) the iron maiden was also great, no one would have solved it if it weren't for... such intellectual monsters...)
As for roles, you also need to keep the number in mind.

За всем следят машины благодати и любви.