I'm seeing a lot of threads about cost of high level breeding dens and stratagies. Although I have not unlocked that unit building yet (@ lvl 41). I have all non-gem related buildings except 2nd manor (1st is still being built since I just unlocked it) and almost all unit buildings to lvl 10 with the exception of Wizard Spire which is lvl 8 and being that it will be by next upgrade. I have been working on unit building upgrades first before economy upgrades (5605 iph atm). My question is when does whale levels start? I'm fairly sure I will not have a problem since I have rarely been beaten in an attack (lost 1 battle 35 days ago, only blemish in my news feed) but would like to hear from upper level players.