“ When was the last time a character caught a cold or flu? Real people get them every now and again even with solid heating and dry interiors. Your characters are out in the cold and wet, and even inside is not always dry and warm. Imagine having to stop your dungeon crawl, sitting in a tight defensive position, while you all are feverish.”
“ (Apologies to GRRM and HBO)
A group of northerners want to bring the Old Gods back to the south. They grow cuttings from the white trees seeking the blessings of the Old Gods on the project, and when the saplings are big enough, they carve faces in them and secretly plant them in forests all over the south, to extend the 'reach' of the Old Gods.
The plan works of course, but the trees are *baby gods*, and behave as such when invoked.”