Dance Assassin's Creed Origins, just like weapons, mounts have rarity levels, ranging from rare (blue) at legendary (golden), and it's not necessarily easy to know how to unlock legendary mounts.
Legendary mounts are just like weapons: you can Win by completing certain quests (e.g. winning all elite tournaments of the Hippodrome to win the Roman War Horse) or by buying to stable masters.
For this second option, it is necessary beforehand to have the competence Back shop to have access to better items at the merchant and thus be able to buy legendary mounts, available at various locations for the price of 5 000 drachmes.
Unlocking the Back Office will cost you 5 or 6 skill points, depending on the "path" you follow
Note that the rarity of mounts has nothing to do with their abilities or stats, but is purely aesthetic. Moreover, it is necessary to change region if you want to see the different mounts available for purchase, always available in pairs (one horse & one camel).
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