I am not sure if I should just level them up and sell them or if I should evolve them once and use them to level up other birds. Also, I recently saw a video where a player was using level 51 shiny birds to level up lower birds. Is it best to lebbqek up a 3* shiny bird to level 51 and then feed it into the 4 and 5 star birds? I've been using the 1 and 2 star shiny birds after the first evolution. Looking forward to some feedback. Thanks!