Quality

Items and guns in the Gungeon belong to five different qualities, which determines their relative rarities.

Certain items have multiple qualities, and can appear in several different types of chests.

=Quality Frequency= Each floor has a unique distribution of qualities for both chests and bosses, with chances for higher quality items increasing on later floors. There are two different loot tables within the game, the Original loot table (which was the loot table before the Advanced Gungeons & Draguns update) and the Gungeons and Draguns loot table. These can be switched between in The Breach or title screen in the Gameplay menu of the Options menu. These loot tables only affect chest quality chances; boss drop chances are no different between loot tables.

Bosses
=Magnificence= Magnificence is a hidden stat that prevents too many or  tier items from being acquired in a single run.

Mechanics
Two factors contribute to magnificence:


 * Picking up any item or gun of or  quality increases magnificence by 1.
 * It will only happen the first time that particular instance of the item is picked up, so it can be dropped and picked up without further increasing magnificence.
 * The increase is permanent and cannot be removed by dropping, selling, or destroying the item. This magnificence counter will carry over to the next floor.
 * Each red or black chest created during floor generation increases "chest magnificence" by 1.
 * Opening one of these chests (and only these chests, not any other red or black chests that may have spawned on the floor) decreases chest magnificence by 1.
 * It is currently unknown whether or not the magnificence from unopened chests carries over across floors.

Whenever the game wants to generate a floor reward item (be it a floor generation chest, a room clear reward chest, a boss reward item, or a shop item) and the result turns out to be an or  tier reward, the quality has a chance to be downgraded. Magnificence and chest magnificence are added together, and if the resulting number is 0, the reward will not be affected. If the number is above 0, the chance that the reward quality is downgraded rises logarithmically.

The exact formula for the downgrade chance is:

The first few values for the formula are:

If the reward is downgraded, the quality of the item or chest is rerolled with the same chance distribution as before, but without the chances of it being or  quality, resulting in a chest or item of, , or  quality.

S
­ Class items and guns are the rarest, and can be found in black chests and rainbow chests.

Guns

 * There are 21 quality guns.

Items

 * There are 17 quality items.

A
­ Class items and guns can be found in red chests and rainbow chests.

Guns

 * There are 44 quality guns.

Items

 * There are 49 quality items.

B
­ Class items and guns can be found in green chests and rainbow chests.

Guns

 * There are 70 quality guns.

Items

 * There are 73 quality items.

C
­ Class items and guns can be found in blue chests.

Guns

 * There are 68 quality guns.

Items

 * There are 71 quality items.

D
­ Class items and guns can be found in brown chests.

Guns

 * There are 30 quality guns.

Items

 * There are 49 quality items.