As far as I know, in the DC universe, at least three reboots have occurred. At first, there are infinite Earths. Then there are 52 universes. The old 52 becomes the new 52. It seems recently, after the Metal event, reality is being reshaped again.
After each reboot event, old stories are "erased" and almost all characters are replaced by new versions, if not eliminated. However, I wonder if there are any characters that survived the reboot event. I mean, are there any characters
- do not die in the reboot event;
- and are not be replaced by a new version;
- and retain their memory of the stories and events before the reboot.