heres one of the secrets that u can find by chatting with the writers but i guess u missed ur chance like 4/5 years ago! before vivi "stopped" and before all the other mages "stopped" the mages and the genomes gathered around vivi and made clones of vivi that will last longer for like 120 years and so. (i am not making this up, go ahead and ask hisashi suzuki yourself, but that is if u can)