Treasure Chest

Treasure Chests are items that can be dropped by bosses. They can contain a number of things, including weapons, passive items, coins, and, if the conditions are met, evolutions. 
==Mechanics==
Chests will most commonly contain one item, but have a chance to contain three or five items instead, depending on Luck. Typically, chests will contain a random weapon or passive item the player currently has, leveling up the item by one. Chests containing more than one item may contain the same item multiple times, in which case the item will be leveled up the appropriate amount of times. In addition to whatever items a chest contains, the player will also receive a random amount of gold.
When the requirements for an evolution (or union) are fulfilled and the run is at 10 or more minutes, chests can evolve (or unite) a weapon. Generally, only one weapon can be evolved per chest, including the higher tier chests. There are a multitude of exceptions for which chest can evolve weapons and evolve more than one at a time, see more in evolution and Arcana.
If all items are at max level and no evolutions are possible, all items in regular chests are replaced with Big Coin Bags (). The Treasure Chest will also randomize the amount the player will receive, which is normally around 150, but this number grows based on how many items you received in said chest and multiplied by Greed. If the player picks up a treasure chest that would only give them coins, the full treasure animation is replaced with a short overworld animation showing the amount of coins gained.
The first six chests picked up in a save will always drop items in the set sequence 1-1-3-1-1-5. These first six chests' animations cannot be skipped. After the first six chests, the animations of chests with one or three items can be skipped. Five-item chests' animations will be skippable once the player has seen the final fireworks, collected 50 five-item chests, or collected a total of 500 chests.
==Types==
===Bronze===
Bronze chests are incapable of providing weapon evolutions or unions. They are typically obtained as drops from bosses spawned before 10:00.
===Silver===
Silver chests are capable of providing weapon evolutions and unions. They are typically obtained as drops from bosses spawned after 10:00.
===Arcana===
Arcana chests provide the player with an Arcana. Will provide two additional items if the player has Game Killer (0). They are typically obtained as drops from bosses that spawn at 11:00 and 21:00.
===Black===
If the player has not yet maxed out all of their items, black chests function identically to silver chests, except they will always contain only one item. If all items are maxed out, in place of a Big Coin Bag, black chests can provide the player with a new passive item that they do not currently have and that is not banished. If the player has Game Killer (0), black chests can provide multiple new passive items at once. They can only be obtained as drops from the large Unknown boss sometimes spawned by Moonlight Bolero (VI).