Instead of refreshing her res cooldown, her ultimate will increase res range
If you haven’t been playing Overwatch recently, Mercy has gone through a few big changes. Most notably, her ultimate was altered so that it no longer resurrects an entire team (that was moved to a new ability that targets single heroes), but rather, boosts her innate abilities and allows her to fly. That ultimate, Valkyrie, is also being tweaked as we speak in the public test realm (PTR).
As explained on the official forums by Community Manager Josh Engen, Mercy’s will no longer get a free cooldown reset after using her ultimate. In other words, players could use resurrect, hit her ultimate, then resurrect again in quick succession. Ultimate cooldown resets are fairly commonplace in games like MOBAs and hero shooters, but in this case Blizzard decided to tone it down a bit.
Instead, Valykrie will now double the range of resurrection, forcing players to be a bit more tactical with their decision to raise a team member. We’ll see how it plays out in the PTR, but for now it seems like a good enough swap.
Mercy Changes [Battle.net]