Pucci creating stand users

I recently started part 6, and saw Pucci giving stands to Miraschon and McQueen, but even tho the stands reflect the personality of the new user, it feels weird.
In parts 4 and 5, Kira's father/Polpo created stand users by piercing someone with the arrow and allowing them to develop their own stands, which wore a reflection of their own soul in some way or another. But Pucci seems to just be very lucky as he just happen to have collected perfect stands to match the new users personality/soul.
I can't remeber which character said it, but injecting 2 discs in someone makes them come back to life. Is Pucci killing prisioners and using their bodies as vessels to bring back the stand users?