This WA pops up an icon when you should use Black Ox Brew. The standard conditions I set are ISB/PB = 0 charges and player energy <= 50. These are easily editable to your preferred conditions (just head to the trigger section and change the values). If Black Ox Brew is not ready it shows the cooldown remaining instead.
EDIT 10.07.2017: Added another condition: KS must be on CD.
This is a collection of 2 auras:
Black Ox Brew USE (icon)
Black Ox Brew CD (icon)