Mercy is one of the most-played heroes in Overwatch, but Blizzard doesn't like how people use her. As director Jeff Kaplan points out, Mercy turns into more of a passive experience once her ultimate ability is almost ready. It's beneficial for her to stop healing and to wait for the right opportunity to resurrect as many of her teammates as possible.
That's why Blizzard's reworking her build in a big way. The goal is to keep Mercy players engaged, and that's why her Resurrect ultimate is being moved to a common ability that's available on a 30-second cool-down timer. However, Resurrect will only be able to target one person at a time, so it adds a new strategic element of figuring out who's the best person to bring back to life.
Taking Resurrect's place is a new ultimate called Valkyrie. The most obvious trait about Valkyrie is that it lets Mercy fly. As Kaplan says "I don't mean she can Pharah boost in the air briefly, I mean she can fly. It's super fun and you have complete control of your character. Mercy has those wings, we might as well put them to real use."
via destructoid http://ift.tt/2xgy0Oy