Cosmetics entails all equippable, "only visual", items in The Horus Heresy: Legions.
"Only visual" refers to the fact that non of these change the gameplay in any way, and only serve as a "treat" for Players to customize their overall look in the game.
While you can just ignore all these items and play as it is, Cosmetics help to make your precense "unique" in the game, by conmbining them in your preferred style or by doing a "lore accurate" recreation (all Salamanders Cosmetics, for example), or even just to enjoy the artwork.
You can get any of them from almost all Crates, or buy them from the Shop/Web Shop.
List of Cosmetics[]
● Avatar[]
Can be viewed always. Your "proxy" face in the game.
● Card Back[]
Can be viewed when in Battle. Change the look of the back of the cards in your Deck.


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● Badge[]
Can be viewed always, on top of your Avatar. In the Battle Report, you can see the full resolution.
● Warcry[]
Can be viewed in the Battle Report, or during a match (click in the opponent name). A famous quote from a character of The Horus Heresy.
—These items (called "regular Cosmetics") can be equipped from the Player Menu.
● Premium Cards[]
Can be viewed in Battle, if added to the used Deck. Gives cards a visual "flare".
If a Card you play, that creates other cards, is of the Premuim version, these new cards will come out as Premium as well.
—You can view your available Premium Cards in the Collection tab.
● Alternative Art[]
Can be viewed when in Battle. Change the look and quotes of the Warlord.
If you don't own that Warlord originally, you only be able to use it for Legacy play (till you get said Warlord).
—You can view your available Alternative Arts in the Collection tab (click on the Warlord that haves it), and equipp it in the Deck Manager.
● Achievements and Level Prestige[]
Both could be considerer "semi-Cosmetics", as they also change your visual output.
—Achievements can be viewed and equipped from your Player Menu for any Player to see. The Level Prestige applies by itself after reaching the corrensponding milestone.
Collection[]
You can all "regular Cosmetics" from any free Crate (better chances in Event Crates), get them (randomly) in Cosmetics Crates, or buy the ones available in the daily Cosmetics tab of the Shop.
Premium Cards might appear in any Crate, or you can buy them from the Collection tab (click in any Card and the "Premium" option will appear) for four times that card cost (Rarity) in Gems.
Alternative Arts can be bought with real money in the Web Shop. Some (free) Battle Passes might reward them (very rare).
Achievements are added to your available list after completing the corresponding challenge.
Support[]
If you have any trouble or problem with a purchase, contact the game Support trough this Link, or from the game itself (Settings→Support).