I've been wondering for some time about what the best point is to sell a pure essence. Do you sell late and get the highest possible sale value, or do you sell early for a lower sale value and accumulate interest? Unless I'm misunderstanding something, the optimal selling point is wave 38, where one gains 11535 moneys (interest till fruit round included). See the full comparison here: https://gist.github.com/JeroenDeDauw/1bd9268205ade939dfb9 The one input there I'm not sure about is the wave duration. This varies. Playing in a way that keeps waves alive as long as possible without losing lives is advantagous, so you might want to run the scrip with a different value for average wave duration.