I wish I had read this two days ago. My party just slapped strahd silly with the sunsword/thighbone combo and vaporized him at the top of the tower by the heart
It was a good flight,climactic and all, but I think if they'd had to trek all the way down to the catacombs and figure out how get...
I would suggest having an encounter while the PC's are sleeping, assuming they have a house in town that they're using.
This is intense, and creepy, and robs them of any feeling of safety, at least for a while. Strahd showed up in my campaign while the paladin was on watch, charmed her, had...