: It was Phelot who decimated Avon's Grove. And those
: Thrall aren't the bodies from Avon's Grove - Thrall
: are made from centuries-old, dessicated corpses.
: Ghasts are made from the freshly dead. But they are
: undead nonetheless, which gets the point across that
: the dead of Avon's Grove sat up and walked off with
: their killer-masters.
According to the Shade flavor, all the dead of Avon's Grove were either made into Thrall or given to the Ghôls as food. We don't know how many met either fate, though (could be 0 for one of them.) Phelot could have made them into Thrall by having them embalmed or just waiting a while. Very fresh corpses aren't Thrall fodder, but they don't have to be* years* old either. Note in the Thrall flavor how they can be made from fairly recently slaughtered civilians.
--SiliconDream