We are looking into the health issue - guess it was something even more complicated. We`ll try again in the next patch
With Unicorns - and same with Ogres - had to do it, otherwise level 5 buildings could quickly and cheaply provide unicorns that could be soled for 3X profit, instead of 30% we want. Really minor annoyance though
And check Uttal Ators - it`s a place to sell Unicorns for a profit.