I only now noticed that the part about humidity did not get copied.. so here it is:

Q: How much humidity they require?! No one ever mentions exact humidity with these snakes!

A: Russian ratsnakes are very smiliar to corn snakes in this part of the care. As long as the humidity is below 80% they will be perfectly fine (higher humidity could cause health problems like blisters for example). I recommend using water bowls big enough for the whole snake to fit, this way they will be able to bath before shedding or when they feel it's too dry. Personally I never heard of anyone having problems with shedding in this species, so antyhing between 30% to 80% will be okay in my opinion.