The Payload
The only way to trap the Reaper was to use the payload as a bait. The Reaper will try his very best to take control of the Payload. The Payload was the best tool Zenyatta could use as bait for the Reaper.
Zenyatta got the help of Reinhardt to help him set the trap. The Reaper has to get into the Payload and Reinhardt will use his barrier field and trap the Reeper in the payload. So they begin to work on setting this plan to action..
They did everything as planned and as expected they managed to trap the Reaper in the Payload. Zenyatta came and confronted The Reeper, but Reaper tried to escape by using his wraith form, but Zenyatta was ready for that. He blasted the Payload with his power of transcendence!
source from Overwatch wiki
Using this power on another object will make every being around that radius unable to use their powers. (Zenyatta in this transcendence state can't use his other powers too) But it won't last for long. Zenyatta only has around 6 seconds before Reaper gets his powers back.
Reinhardt does his Earthshatter and puts the Reaper down! Zenyatta then gets to work and begins to hypnotise the Reaper with the help of his orb of Harmony and when The Reaper awakes he'll be purged from all his evil and work for the common good!!
Did it work? Well that's another story..
Fiction inspired by Overwatch...I don't really play Reaper much, so I kinda suck playing him, but if you wanna have an idea of the gameplay, you can check out my very bad gameplay video below :)
Story written for @mariannewest's freewrite challenge. Check out her blog and join our freewrite community.