Grinding for cores doing the same old stuff. That’s just it. It is the same same old stuff. So if you don’t want to play the same old stuff there are no reasons for you to worry about cores. Honestly they drop more frequently now plus if you are in a clan at level 4 or whatever you get 7 per character for doing your clan milestone. It is not the cores it is the staleness of the game. If there was something to make people want to play they would do what the have to do to get. Unfortunately there isn’t.