These days Blizzard Entertainment is all about balancing various characters with every other Overwatch update, which is why when people saw a change in the way Mercy plays, they thought it was an undocumented nerf to the character. But that is not the case.
The issue popped up a day ago, and has been widely reported on the public test realm related threads of the game, where the developers had to jump in to clarify what exactly was going on.
The first person to report on the issue was a forum member on Battle.net who explained exactly what was going on, and also that there was no mention of the Mercy Nerf in the Overwatch update notes for the PTR:
Mercy’s staff no longer holds on to the same target when switching between healing and amping damage regardless of line-of-sight or where the player is looking. Playing Mercy now feels a bit clunky if I’m switching between beams constantly.
In other words “prior to this patch, when healing/damage boosting an ally, you didn’t need line of sight or to be facing your current stream target to switch to the other stream. Now, if you want to change streams on your current target, you need to reacquire the target completely.”
However, Geoff Goodman, the principal game designer on Overwatch quickly clarified that the changes people experienced were not intentional.
In fact, Blizzard Entertainment says that this is a bug that they are working to fix as we speak. Goodman even apologized for the trouble and said the fix will be out “asap.”
The latest character to get nerfed in the upcoming Overwatch update is Torbjorn whose turret is going to get less damaging. Before this, Widowmaker and McCree were also nerfed by the developers.