Forgot to still comment about the Cathedral disappearing. I was thinking of rumbling etc. at beginning, but those would have needed some more work to get done. I went with transparency disappearance, since I was already using that all around there, therefore it was quick to implement and a cheap effect from making point of view.
It also worked thematically, since idea is that, while you might not really notice it, due to the coloring of the cathedrals, they are actually all in full color and full light. I think I told AI to do it that way, so the player wouldnt necessarily notice that they are in full color and light. For idea is that these cathedrals are not from this world, but they are heavenly things. Therefore they are not affected by the loss of color or light, since they themselves are it.
Also, one of the things is that places of all these cathedrals are known to people of the world, and therefore they could see there are colors and light there, but they have chocen to ignore it. Similarly as we have bible which tells how to live and have a good life, but most people ignore it. They know where to find it, from the bible, but they dont read it. Therefore, similarly even these cathedrals are, and have always been in full color and light, people are ignoring them, and therefore not seeing their colors.
And therefore this transparency fading was suitable way to tell the damage, as enemy cant hurt them, but they can hurt you, the player, to not see them anymore.