These will be the Dragonball Zero characters that'll appear in the series. I just put the names here since, if you read the book(s), you'll know who they are. I'll also add names that haven't appeared in the book for your imagination to decide who they are

[Characters that have appeared]
Yanzo
Lon
Vergil
Mavel
Chip
San-su
Hael
Android 48
Dr. Bernie
Naime
Fang
Leon
Jax
Koa
Android 105

[Characters mentioned but not seen]
Terra
Hydra

[Characters that have not appeared yet]
Kon Krete
Ize
Android 1
Vex