In a recent PTR build, Blizzard has added a new reward to achieving Gladiator in Season 2 — A Dragonriding Manuscript that unlocks the unique mount appearance as a Total Transformation for your Winding Slitherdrake. This system is already in place for Dragonflight Season 1, so it just equates Season 2 to Season 1.
Win 50 3v3 games while at Elite rank during Dragonflight Season 2. Read more on wowhead.com