Shows transparent icons for AoE taunt and Intimidating Shout on Kael'thas after phase 3 (four advisors) has started. The idea being that you get everything on CD before phase 4 starts.
Not sure if there would be a reliable, better, later trigger to use before phase 4 starts, like checking for deaths of 2-3rd killed advisors like Sanguinar, would need some testing to make sure that works and isn't weird with phase 1 "deaths".