The Heralds on Proving Day

In the modern series that we're looking at now, the heralds are around, or at least nine of them are. The chalon talks about their being a proving day where they had to somehow earn their place as haralds. That kind of makes us think that they probably did have to perform very difficult tasks on that day. But their personalitys seem to be deteriorating, falling aparta, getting worse. They either like the worst version of themselves, or some sort of perversion of their initial intent.