I've put together a list of names great for a black horse, from mythology to race horse names to words from different languages meaning something black.
100+ unicorn names with meanings from movies and popular culture
139 Black Horse Names: You Will Love!
100+ black horse names that are beautiful and unique
Unique horse names
100+ unique black horse names with meanings - My life is better with horses
120+ Black Horse Names From Powerful to Sweet
120+ Black Horse Names From Powerful to Sweet
200+ Magical, Mystical Names for Cats - PetHelpful
180+ Names for Black Horses - Helpful Horse Hints
400+ Black Horse Names: A Comprehensive Guide for Your Dark Beauty
Black Horse Names: Ideas for Dark Horses
400+ Black Horse Names: A Comprehensive Guide for Your Dark Beauty
33 Good Black Horse Names (With Meanings)