Btw what I find super-annoying: Everyone completely ignores the fact that all those "dead" people were ... well, DEAD! But they seemed fine. Why did nobody ask "yo, whatīs death like? Did you meet Kaio-sama?" Stupid.
Well, Haku and Zabuza had exchanged a dialog along the lines of "Hey Zabuza-san, are we in Hell?" "No Haku, it seems someone brought us back to life." So maybe they have no recollection of the time between their death and their resurrection.