Mac: bad performance since last patch

[Impomea-1347]

I think this is what you are looking for.

Latest patch on 8th October makes my mac very sluggish

I was also having this issue on 2015 MBP with Retina since the wild cards update. Extreme lag and crazy fans. I saw this fix on Hearthpwn by user Flanderok and it fixed all the lag and fan issue. Go to Applications-> open Hearthstone folder -> right-click on Hearthstone icon -> get info -> check the box “Launch in low resolution mode (basically disable retina scaling for the app)”.