AD item Grievious Wounds is probably an effort to keep Sated Devourer reasonable.
Sated Master Yi and Xin Zhao are the two most overpowered Sated users in League right now, they need constant CC locking to take down which is just too much resource investment when you pair a Riven or a Fiora in the same team as that jungler Sated Xin or Yi.
It seems that Riot is trying to keep the badly designed item of Sated Devourer in the game by re-introducing Grevious Wounds for AD champions which should even out the Sated game. Wish they'd done that sooner.
Side note: Grevious Wounds should not be instant 50% healing reduction. Grevious Wounds could be a stack mechanic similar to Black Cleaver's passive so that you don't instantly over power champions designed wholly around healing such as Aatrox, Vladimir, Dr. Mundo and Soraka.
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