Booster Pack rarities were introduced in the Xmas Update on 15th Dec. 2016 What rarity means is that some items in the Booster have smaller chance of getting rolled as one of the three items you get when you buy the Booster. The specific rarities for common, rare and ultra rare items vary between Booster Packs as some Boosters have more items than others. The rarities has been updated on the Easter Update on 12th April, 2017. Now the existing Rarities are Common, Uncommon, Rare, Ultra Rare, and Legendary This rarity applies only to Boosters. Items that players have do not have any set rarity as that would be impossible to determine because in Portal Worlds players create the economy themselves by bringing more items into the world.