Mystery Crates are another alternative way to acquire bundles of Cosmetics. Every time you win a match, you have a chance of winning a Mystery Crate filled with Cosmetics, Prismatic Cards, and game content.
Opening a Mystery Crate requires a corresponding Key. You may buy more keys from the Mystery Crates menu.
Remember, cosmetics can always be directly crafted or purchased from the Armory, but the Mystery Crates provide another method to acquire high-rarity cosmetics. Duplicate cosmetic items dropping from crates will be disenchanted for a fraction of the Spirit cost.