The drop rates for the poppy shrub is low too. I don't know if it's worse to make the shrub in the arboretum or to keep the 40 poppies on the board. I am only spawning one bat per lava formation. At $100K a pop, that doesn't really seem fair when you need 40 gems to level up. I'm half way through this and the diminishing returns of this .... I don't know. This one seems a bit too much. I normally don't mind the boring, tap tap tap games they make, but this seems to be without reward. And expensive. And to answer the person above, I see that the lava formation is only available for 3 days, too but I'm sure they will extend because this game is going to take forever to complete.