the previous theory i did for the Talon Tracer was bad, so i redid it, here it isTracer was actually forced to attend the Slip-stream experiment because no one was volunteering. The scientists thought to put the 19 yr old Lena (aka.Tracer) to the test, if the test goes wrong and Lena died no one would pay great attention to it (since shes not that well know yet) . They put it the forceful way like " Congrats, Lena you've been selected to be the first to do the experiment". Lena of course, who is young and passionate agreed the offer. The test went wrong, Lena disappeared and once she was back she appeared to be in a coma on the side of the street. Coincidentally, Reaper just happened to be roaming the street, he found Lena lying on the road and took her back to Talon and helped her recover. (Reaper can have body contact with the ghost Lena simply because he is the god of death and he has the strong ability to do so.). After Lena recovered she felt shit, deep down in her heart she knew that the Scientists from Overwatch used her as a sacrifice and even after she went missing they did nothing about it. She then wanted to take revenge and became a part of Talon. Talon’s member helped Lena develop the chronal accelerator to keep her in the presence and implanted chips into Tracer, which can help her have the ability to recall and blink even she takes off the chronal accelerator. ( the chips on her face help Tracer to live even without the chronal accelerator for a short amount of time, it can be recharged, this grants Trace more mobility.)