I like the idea of a faction having a one-time ability similar to the scoundrel's torch. Also the artwork is both cute and terrifying.
I think the numbers are a bit difficult to parse, partly because I don't know what you have as your warrior supply. Do the sacrificed souls need to scale like that? For a game as short as root is, I'm not sure there should be anything besides the scoreline and army supply that exceeds 7-9. Think of the duchy ministers, moods, roosts, sympathy, etc. I would probably trim this down to fit within the complexity budget of Root.