Dungeons

Dungeons include forests, caves, buildings, and other places that are accessible by spending Dungeon Tokens in which wild Pokémon are encountered. Apart from the entrance fee, they differ from routes in that only 60 seconds are given to find and defeat a "Boss Pokémon" or "Boss Trainer", after which the dungeon is considered cleared.

How to clear
Clearing Dungeons requires active play. To enter a dungeon, select it on the Town Map and either click "Start" or press the Spacebar on the keyboard. Dungeons can be navigated either by clicking on the dungeon tiles or by using the arrow keys or WASD keys. Only unexplored tiles adjacent to explored tiles can be accessed. Moving to unexplored tiles in dungeons can reveal one of 4 things: Note: Amulet coin and other items that grant increased amounts of do not affect the amount of money that you receive from Dungeon Trainers or Dungeon Trainer Bosses.
 * 1) Empty tiles - You can simply move onto next tile without having to do anything.
 * 2) A Wild Pokémon - Just like routes, these are Pokémon you can defeat and catch. Some Pokémon can only be found in specific dungeons.
 * 3) Dungeon boss - This Pokémon must be defeated to clear the dungeon. It has more HP than normal encounters in any dungeon. You can either click "Start Bossfight" or press the Spacebar to start the fight.
 * 4) A chest - Battle Items can be collected from chests by clicking on them or by pressing the Spacebar.
 * 5) A trainer - Trainers are found on tiles and have teams of Pokémon that must all be defeated to progress. Wild Pokémon are almost always ~4 times more likely to appear on an enemy tile than a trainer, but in some dungeons this weighting is different. Defeating trainers yields the following rewards:
 * 6) * Dungeon Trainers reward 4% of the dungeon cost as Dungeon Tokens and 50% of the dungeon cost as Poké Dollars  whenever they are defeated.
 * 7) * Dungeon Trainer Bosses reward 10% of the dungeon cost as Dungeon Tokens and 100% of the dungeon cost as Poké Dollars  whenever they are defeated.

Dungeon Size Reduction
After clearing a Dungeon a number of times, certain perks are granted to the player in that Dungeon to make clearing it easier. When the number of clears reaches a power of ten (10, 100, 1000, etc.), the Dungeon size will shrink by 1 row and 1 column to a minimum of 5x5. For example, a Hoenn dungeon cleared 100 times will now be a 5x5 sized Hoenn Dungeon instead of the base 7x7 sized Hoenn Dungeon.

The number of each type of tile decreases with the size of the dungeon. All dungeons will be square. Here is the breakdown of each type of tile based on size: For an NxN dungeon there are: $$ \text{1 Boss Encounter Tile}$$ $$ \text{N Chest Tiles}$$ $$ \text{2*N+3 Non-Boss Encounter Tiles}$$ $$ \text{(N+1)*(N-4) Empty Tiles}$$ Note: The entrance tile counts as an empty tile

Flash Ability
A Dungeon that is cleared 200 times will unlock the Flash ability, which permanently reveals the contents of adjacent unexplored tiles.

Chests in Dungeons
When a number of chests equal to a third of the dungeon's size rounded down are opened (for example, 2 chests in a 6x6 dungeon), all chest tiles are revealed. When a number of chests equal to half the dungeon's size rounded up are opened, the entire dungeon is revealed. However, each chest opened will also increase the HP of all encounters in the dungeon by 20%.

Dungeon Loot Debuff
When the furthest region reached is greater than 2 regions beyond a dungeons region, all loot below Weight 2 has its drop rate dramatically decreased. If the furthest region reached in the game is Alola, then all loot below weight 2 in Dungeons from before Unova, i.e. Kanto-Sinnoh, would be affected by this debuff.

As an example of how that would affect a dungeons loot weight table, Viridian Forest has six dungeon chest drops. Three of those, Small Restore, Grass egg, and Leaf stone all have a weight below 2. After reaching Sinnoh all three of those loot drop items would be impacted by the dungeon loot debuff and would become roughly 20x as rare. The chance still increases with dungeon clears as that still decreases the chance of finding weight 4 items up to 500 clears, but it is much better to go for drops before you get this debuff.

Kanto
Dungeons in Kanto are 5x5 in size (25 tiles in total), contain 5 chests, 13 non-boss encounters, and 6 empty tiles.

Johto
Dungeons in Johto are initially 6x6 in size (36 tiles in total), contain 6 chests, 15 non-boss encounters, and 14 empty tiles.

Hoenn
Dungeons in Hoenn are initially 7x7 in size (49 tiles in total), contain 7 chests, 17 non-boss encounters, and 24 empty tiles.

Sinnoh
Dungeons in Sinnoh are initially 8x8 in size (64 tiles in total), contain 8 chests, 19 non-boss encounters, and 36 empty tiles.

Unova
Dungeons in Unova are initially 9x9 in size (81 tiles in total), contain 9 chests, 21 non-boss encounters, and 50 empty tiles.

Kalos
Dungeons in Kalos are initially 10x10 in size (100 tiles in total), contain 10 chests, 23 non-boss encounters, and 77 empty tiles.

Alola
Dungeons in Alola are 11x11 in size (121 tiles in total), contain 11 chests, 25 non-boss encounters, and 84 empty tiles.

Trivia
To complete all dungeon achievements, you would need following amount of Dungeon tokens