Dungeons is a game mode that adds a choose your own adventure feeling to the game.
in order to start a dungeon, the player must have a dungeon key which can be obtained through Daily Quests, the gambler npc outside of Summon.
upon starting a dungeon, the key will be consumed, and the player will be granted 3 choices, the three Tiles on the bottom show you what loot you will get for winning that Match, the Tiles on top of the bottom Tiles show what games you will be able to choose next, choosing a different bottom Tile changes what your next Match options will be.
through playing the dungeon games the player is able to receive rewards like hoard, chests, and rare chests.
when choosing which game to play there will be smaller Tiles in the option Tile telling you what your rewards will be, theses Smaller tiles can be any of:
The Hoard Tile, upon completion, will give you Currency called 
Dungeon Money, which can be used in the Shop Tile
the shop Tile, upon completion of that game, will open a shop ui which allows you to spend your Hoard in return for blessings
The Curse Tile will add a curse to your Dungeon inventory. More information about the curse can be viewed by hovering over the tile.
the Chest Tile, upon completion of that game, will give the player a chest
the Rare Tile square, upon completion of that game, will give the player a rare chest
Upon completion, you will have the ability to open Treasure Chests or Rare Chests. It is recommended to NOT open Rare Chests before the end, since you'll have a chance to get a Secret Unit.
Treasure Chests can give Stat Rerolls, 
150 Gems150 Gems, and 2 Star Remanents.
450 Gems450 Gems, 5 Star Remanents, Curse Tokens, and the chance for a Secret Unitthe Relic square, upon completion of that game, will open a Relic UI, where you can choose to take a relic or not, relics can give both curses and blessings, and the relic will tell you what the curses and blessings are
if the player loses a match, the player will have 4 more chances to win that match, if the player fails to do so, they lose the dungeon
in order to complete a dungeon, the play must win 20 games