What is your experience and what do you think is the strategy with the best XP/coins ratio? I really don't know what is best but what I've been doing is leveling up 2 or 3 stars shiny birds of the desired colour to level 20, evolve them and use them to level up my 4-5 stars birds on Thursdays when XP is doubled. Then for the prestige levels it's super important to use them on Thursdays as well as they are limited and you need so much gold. Last Thursday I leveled up birds and used prestige totems thinking it was the end of daily bonuses but now it looks like they are back...what a waste! I'm not so fan of these xp thursdays actually as it "lags" (slow down) the game quite much if you want to wait for them to optimize...but this is another story!