Breath of the Dying is very cool Azerite Essence. In Major, this Essence is BIS for most MDD in Ny'alotha (like on Drest'agath).
As you know, if you use it on target who has less than 20% health or more than 80% health, the cooldown is reduced by 30 sec.
But the problem is what you should (always) look at % of the target and on panel with button the same time to understand, can you use it right now or not.
Well, this WA shows the icon if ability is ready and if target has <20% or >80%.