Old Mercy (as in Mercy 1.0, when her ult was an AoE rez) was acually considered to be the weakest healer once you got out of the low elos. She was a virtual ghost in the highest levels of play, and the pros didn’t use her at all outside of the occasional desperation Pharmercy strat.
I know that to some, this sounds crazy. I can hear it now:
“But she had mass rez! That had the potential to bring back the entire team!”
Stop.
Rewind that sentence.
Pause on the ninth word:
Potential.
If you’re judging an ability by it’s potential, every single abiltiy in the game is too powerful to exist.
Every source of damage has the potential to wipe out the entire enemy team. Every stun, knockback and debuff has the potential to completely shut down an enemy push. Even any source of healing has the potential to keep a teammate alive forever.
But that’s on paper.
In reality, you rarely ever get that sort of opportunity. Sure, sometimes the stars align and you get to make an amazing play that immortalized in a highlight video, along with the many other people who got that one opportunity in their dozens of hours of playing that hero.
If you judge by highlight videos alone, Reaper always kills the entire enemy team with his ult. Widow always wipes the floor with her enemies by getting headshots every time. Lucio always boops the entire enemy team off the map.
But how many times does that happen to you?
Mercy 1.0 had a pretty cool ult, but without an E abiltiy she had zero use in the midfight, before anyone got their ult. Meanwhile, all of the other healers bring a lot of utility and damage to the table on top of their healing, and that’s not even counting their ults into the equation. They could make clutch plays, help the team push, and shut down the enemy with their base kit alone.
Mercy 1.0 couldn’t compete with that. She was nearly entirely dependent on her ult to swing the fight, and even then any observant enemy could undo it by saving an ult to drop on the enemy as soon as Mercy uses her own.
“Why bring a Mercy who MIGHT save your team from a whombo combo, when you could bring an Ana who could prevent the enemy from ever getting the chance?” That was the reasoning back then, for calling Mercy a troll pick.
That’s why one of the most common forum topics pre-rework were pleas for Mercy to get a mid-fight E ability, so that Mercy could be more than just a flying target while she charged her ult. Many even suggested compensation nerfs to Mass Rez, so that Mercy didn’t get over-buffed with the addition on an E.
Mercy was balanced by having a consistent base kit, but a situational ult. She was good on teams that spread across high and low ground, and good on payload maps. She was weak against dive, bad on deathball teams, and didn’t preform as well on control maps. You could force the Mercy to switch by harrassing her with flankers.
If Mass Rez had gotten nerfed to make it feel more fair to play against, Mercy could have gotten an mid-fight E ability as compensation. She could have kept her niche instead of taking over the entire healer category, with this darn rework that’s wiped out all of Mercy’s weaknesses.