Why Vampires are not immune to poison?

I’m doing Curse of Strahd as a DM for my first time any advice?

Do the original Tarocca cards work for Curse of Stahd?

Do you have a favorite non-Barovia-based Ravenloft module?

Is it true that a vampire can’t be a werewolf but a werewolf can be a vampire?

If the Vistani were modeled after Romanian Gypsies then what ethnicity would you say Barovians are?

If Argynvost got Zhudun’d back from the dead, what would happen?