Vicious Black Bonesteed

The Vicious Black Bonesteed was a skeletal warhorse mount earned by winning Rated PvP matches while at a rating of 1400 or higher during Battle for Azeroth Season 2.

In patch 9.1.0, it will become available for purchase from Deathguard Netharian for 1 Vicious Saddle.

Mount Journal
These skeletal steeds know no fear, eat no grains, and can travel impossible distances.