Often my Marans are of the belief that neutral is nearly as sacrosanct as good, and killing a neutral who is "just doing his job" is starting down the path the Dark Side.

Natesthal's backstory was such that he had kind of "had enough" of Orderly behavior, so Invoker guildguard or Spire Captain - didn't matter, you were stopping me from killing evildude.

Smarter evil tribs started hiding in the Paladin guild toward the end...