Items in For The King a classified according to their Rarity. Each item has a quality tier for their respective rarities listed on their card, indicated under the item's name. An item's rarity is also indicated by the color of its card (see Rarity Tiers).
The higher the item's quality tier, the rarer the item is. Generally speaking, the higher an item's rarity tier, the more abilities or special effects it will have or be able to bestow. This isn't to say that Common items are useless either; on the contrary, there exist a variety of helpful items at all levels of rarity.
Some items, such as the Cave Mushroom, can appear with varying rarities.
Quest item rarity is a unique case, as quest items have their own category. Quest items are labeled as such under the item's name, and the card's color will be green instead of the usual rarity color.
An item labeled as a "Quest Item" may not necessarily be tied to an actual quest; the Safety Stone is an example of one such item. All characters begin their adventures with a stone in their inventory, however it is not the objective of any particular quest, nor is there any kind of reward for using or selling the item.
There are five different tiers for Rarity in the game, as follows: