[@HereComesTheSnow]: Well, vampires can be killed by a few things: Complete incineration, being completely frozen, or having enough of the body destroyed and their head severed. If you just cut off the head it won't work, but if you destroy a lot of their body [i]and[/i] take off the head then it overwhelms their regeneration.

Vampires need to have enough mana to be transformed, or else they just die.

And the most fun part... Vampires being hurt by the sun because Reon hates them isn't a joke. Reon hates vampires so much just standing in sunlight is harmful to them. It can't [i]kill[/i] them only because Reon does understand it's not a choice to be a vampire. But she still hates them. Reon has a special hatred for vampires over the standard dislike of undead exhibited by both goddesses(and thus filtered down to the church). Sapient undead are more accepted then vampires as a result, though it's not impossible for a vampire(like Tyaethe) to find a place in human society, it is preeeetty rare.