Too difficult to earn enough keys for quests. I would be curious to know how many people actually achieve the end goal and how many hours of gameplay it took. Update Value appears to have improved on keys. Unfortunately with new updates the game keeps crashing. Ads are too long for the frequency in which they interupt gameplay, as well, the pace in not in alignment with a players ability to progress, unless you pay. Construction is too long on items forcing players to buy gems to finish early.