Well, I find myself far less interested in trying to rank this event as I am interested in grinding tomes to earn Thanatos II. That being said, I was curious what the best difficulty to grind for tomes would be. Is there any actual difference in the chest drops between Rook and Master class? If the frequency and the contents of the chests is equal between all difficulties, then I feel like simply grinding tomes from Rook is the most effective method to obtaining more tomes. Am I correct in this assumption, or is there a massive increase in chest drop rates and the rarity of their contents in master difficulty?