ZOINKS it's like High Noon!

Vel-Mei: Now let's see who The Reaper really is!
[She takes the mask off to reveal Mercy]
All: DR. ZIEGLER?!
D.aphne: But, why'd she do it?
Mercy: I was tired of everyone telling me that they need healing when they could've asked Zenyatta or Lucio instead! So, I dressed as The Reaper to scare everyone away so that they would leave me alone go to those other healers!
McShaggy: But, how was The Reaper able to fly and pass through us like a shadow?
Fred 76: And disappear from one place to reappear in another?
Vel-Mei: That's easy! Holographic projectors and The Reaper disappearing from one area and reappearing in another? Smoke bombs and trap doors giving the Reaper a ghostly appearance.
Mercy: And I would've gotten away with it, if it weren't for you meddling kids and that robot!