I bought the 6* and the 4* max slimes when there was a half price promotion, just for having them in the archives. Still holding them for an emergency evolution that might pop up. I wouldn't go for them thought, as doing dailies provides a fair amount of resources and I rather use the blood gems on the skins I want.
I did lol. Just started building N.Mona
No, even if it was in half price, i wouldnt buy it cause it's too pricey for me