It's kinda difficult The original dredgens were made by Shin malphur and his closest allies to lure out Guardians who would use the light for evil and eventually kill em all in one go The dredgens at their core are not evil, but the ones that weren't the original few were Unfortunately the dredgens are kinda extinct now. I didn't like how the story developed but there nothing you can do [spoiler] Drifter gave out dredgen titles cuz he was working with Shin. He would give Guardians who looked like they were secretly dangerous the title so that eventually shin could kill them. At least that's what I understand[/spoiler]