Is there any better way to introduce the players to the horrors of Barvoia other than dropping them into a cemetery populated by zombies? I used zombies from the Book of Beautiful Horrors. Bloated Zombies, Ravenous Zombies, Hordes, and even a Shambling Lord.
The players discover that Grandma has been captured by the Shambling Lord. With overwhelming odds against them, they must save Grandma and escape to safety. Safety that lies on the other side of the Gates to Barvoia.