Mystery Dungeon game mechanics

The Pokémon Mystery Dungeon series mechanics differ from those used in the core series Pokémon games. The games are  in nature; as a result, some staple elements of the Pokémon series have been altered or excluded entirely.

Pokémon
There are a number of differences between the mechanics of Pokémon in the core games and those of Mystery Dungeon:

Base stats

 * Effort values (EVs) and individual values (IVs) are not elements of Pokémon Mystery Dungeon. Instead, each Pokémon has a set of base stats, which increase by fixed amounts when they level up. Stats may further increase through the use of Gummis, health drinks, Sitrus Berries, and other items. Non-HP stats can be raised to a maximum of 255; HP can be raised to at most 999.
 * Prior to, each Pokémon has a fixed body size that is represented as a number from 0 to 4. When taking a team into a dungeon, the combined body size of the Pokémon in the team may not exceed a certain amount (at most of any dungeon, 6). Note that certain dungeons may restrict this further, and may also restrict the sheer number of Pokémon allowed in the dungeon.
 * The stat did not exist prior to . The Speed stat varies in effect from the core series as it affects accuracy, along with affecting moves like.
 * Movement speed is an aspect of all Pokémon Mystery Dungeon games, not to be confused with the stat. Movement speed determines the number of actions that can be taken in a turn. Movement speed can be altered by moves and Abilities that affect Speed in the core series, such as, , or . Paralysis cuts movement speed in half, and  Pokémon will have increased movement speed in snowy weather.
 * Stat changes from natures do not exist in Pokémon Mystery Dungeon.

Abilities
Prior to Pokémon Mystery Dungeon: Gates to Infinity, Pokémon with two will have both at the same time (instead of just one). From Pokémon Gates to Infinity onward, all Pokémon have only one Ability. In Pokémon Super Mystery Dungeon, Pokémon with two possible Abilities can have their Ability changed at Hawlucha's Slam School if the player has a Lucha Token. No Pokémon Mystery Dungeon series games have included Hidden Abilities.

In addition, some Abilities differ from their counterparts in the core series:
 * Different activation - will only activate when hit by an attack, and the copied Ability is randomly chosen, while  only activates if a Wonder Orb or a special move is used.
 * Minor changes -, , , and will double the power of Water, Fire, Grass, and  moves, respectively, when the user has reached ¼ of their total HP. , , , , , , , and  only affect adjacent Pokémon, even if the move normally makes contact (e.g. , which can attack from 1 square away).
 * Changes to suit environment - reduces the opposing Pokémon's Attack by 20%, while  and  will have a 1/3 chance of dealing 50% more damage.
 * Entirely changed - increases movement speed by one level every 250 turns while  and  use the same attack twice in one turn while it is  or, respectively.  is activated at low HP and inflicts the Run Away status, forcing the Pokémon to avoid attacking and travel aimlessly.

Evolution
Evolution does not occur automatically; instead, it must be manually triggered. Evolution is explained in Story Mode as an effect of the world being in a state of danger. The ability of Pokémon to evolve must be unlocked through the course of Story Mode (in Blue Rescue Team and Red Rescue Team, must be defeated, while in Explorers of Time and Explorers of Darkness, the Wigglytuff's Guild must be defeated). Similarly, in both Gates to Infinity and Super PMD players can evolve after both completing the game and reuniting the main character and partner. In Pokémon Mystery Dungeon Blue/Red Rescue Team evolution does not instantly make a Pokémon stronger, unlike in the core series games; however, as of Explorers of Time/Darkness/Sky, evolution does immediately increase stats.


 * Starting with Pokémon Mystery Dungeon: Gates to Infinity, Enemy Pokémon will also be able to evolve, and will do so if they defeat one of the player's party Pokémon.
 * Super Pokémon Mystery Dungeon was the first Generation VI game in the series and thus features Mega Evolution. It is achieved by attaching an Awakening Emera on to a Looplet.

Because of the different mechanics of Pokémon evolution, certain evolutions have been modified to require particular items:
 * Pokémon that in order to evolve instead require the Link Cable.
 * requires the Beauty Scarf to evolve into.
 * Pokémon that require high friendship to evolve instead require that their IQ be sufficiently high (which differs among Pokémon).
 * and require the Coronet Rock to evolve into  and, respectively.
 * Pokémon that evolve in the daytime instead require the Sun Ribbon.
 * Pokémon that evolve at night instead require the Lunar Ribbon.
 * requires a Mossy Rock to evolve into or an Icy Rock to evolve into.
 * In Super Pokémon Mystery Dungeon, evolutionary items do not exist, and Pokémon that usually require these items to evolve will not need them and be able to evolve regardless.

Recruitment
Instead of catching Pokémon (as in the core series games), Pokémon may be recruited to the player's team. Recruitment rates are different for each Pokémon and can be increased by factors such as the level of the team leader and any items being held. Some dungeons may prevent recruitment while some Pokémon must be recruited by special means. In Super Pokémon Mystery Dungeon, Pokémon are no longer recruited, but must be connected with using the Connection Orb.

Miscellaneous
The Mystery Dungeon series introduced Level 1 Pokémon, an aspect which wasn't introduced until Generation IV of the core series. This may occur for wild Pokémon, guest Pokémon, or new Pokémon who ask to join after a mission is done. Evolved Pokémon may also be encountered at lower levels than those at which they would have evolved.

Most Pokémon, as well as, can walk through wall tiles. While on a wall tile, they cannot be attacked but can attack their foes. However, their belly empties at a rate of 5 per step. Water/Flying Pokémon can move through Water tiles and Fire/Flying Pokémon can move through Lava tiles, Flying Pokémon will sustain a Burn however.

In the Mystery Dungeon series, the player's party size is limited to four Pokémon at a time, instead of the standard six. In Super Pokémon Mystery Dungeon, this is reduced to three, but with a seemingly unlimited number of guest Pokémon at times.

Attacks
All Pokémon have a standard attack which deals typeless damage. This regular attack does not expend PP when used. Pokémon may also have up to four special attacks in addition to their regular attack. Prior to Pokémon Mystery Dungeon Gates to Infinity, the standard attack was much more powerful and dealt damage according to the usual rules using Attack and Defense Stats. However, in Gates to Infinity and later games the move deals 5 HP damage regardless of stats.

Special attacks may be linked together, wherein the linked moves are done in succession (in which case one PP is taken from each move). Moves can be linked at the in Blue and Red Rescue Team and at the  in Explorers of Time and Darkness. Moves could no longer be linked in subsequent Mystery Dungeon games. Instead, Gates to Infinity introduced Team Attacks, large-scale attacks used by every member of the team in a dungeon, while Super Mystery Dungeon introduced Alliances, a simultaneous attack by all party members on a single target.

Many individual moves have differences from the core series games. For example: There are two attacks specific to the Mystery Dungeon series: and. No Pokémon learn either naturally, but all Pokémon that can use TMs can learn them through TM.
 * Some attacks that do specific HP damage (like ) have a different set HP.
 * Prior to, only changes the form of the user, not their moves.
 * and will not necessarily knock out the user of the move. Instead, any team Pokémon within range (one tile for Self-Destruct, two for Explosion) will have their maximum HP cut in half, and any opposing Pokémon within range will receive 40 damage for Self-Destruct and 80 for Explosion. Note that s will receive only half damage from these moves. Any items within range are destroyed, and any wall tiles in range are converted to floor tiles.

Moves that may be used by team members in dungeons can be switched on or off. Certain tactics are also available which will direct how teammates attack and traverse through dungeons. In Blue and Red Rescue Team and Explorers of Time and Darkness, the tactics available depends on the team leader's level.

Damage

 * Type effectiveness has been greatly changed:
 * "Super effective" attacks will only deal 1.4× damage instead of 2× damage as in the core games.
 * Attacks that are "not very effective" will deal 0.7× damage instead of 0.5× as in the core games.
 * Attacks to which the attacked Pokémon is "immune" (called "ineffective attacks" here) deal 0.5× damage instead of no damage as in the core games. However, as in the core games, Pokémon may be immune to certain status conditions based on its type (for example, remains immune to ). Note that the effects of Abilities remain unchanged (for example,  attacks still have no effect against Pokémon who can ).
 * The damage bonus that critical hits provide is only 1.5× instead of 2× in the core games prior to Generation VI.
 * Each move has an inherent Critical Hit rate, which may be modified with items (such as the Scope Lens) or IQ abilities (like Type-Advantage Master). The use of ensures that special attacks used within a few turns become Critical Hits.

Status conditions
Pokémon Mystery Dungeon introduced its own series of status conditions, of which any number may occur at once. These range from the (Paralysis, Poison, etc.) to "" (Confusion, Attraction, Flinching (here called Cringing), etc.). Statuses may be inflicted to account for two-turn attacks (i.e. or ), low-priority moves (i.e., , or ), or moves whose effects last multiple turns (, , , , , , etc.).
 * Duration of status conditions may also differ between Mystery Dungeon and the core series; most notable is that Paralysis, Leg Hold (affected from or ), and most other statuses are temporary. Burn and Poison remain permanent, however all status conditions are removed upon entering the next floor of a dungeon. In addition, Pokémon may be affected with both Sleep and Paralysis, and (much like in the ) other status ailments may replace previous ones. For instance, a Poisoned Pokémon may become Paralyzed instead.
 * Pokémon will never attack themselves while Confused. However, they may move or attack in a random direction (including hitting teammates). Note that Confusion does not affect thrown items.

Experience

 * Defeating a Pokémon using at least one special move will net twice as much experience. Note that an opposing Pokémon using moves on itself counts towards receiving the experience bonus, but using special moves that miss the opponent (or that hit, but do no damage) does not.
 * Defeating a Pokémon using linked moves will net 50% more experience.
 * If an enemy were to faint by means other than the party attacking it (such as by the effects of a ), the members of the party will not gain experience points.
 * All Pokémon in the party gain experience whether or not they attack the opponent.
 * In Gates To Infinity, all Pokémon on the player's team will receive experience, regardless of whether or not they were in the party that entered the dungeon.
 * Pokémon require significantly more experience to level up than in the core series games.

Items
Held take one turn to consume (which must be done manually in many cases), as opposed to being consumed automatically in the same turn that they are needed.

The and   play slightly different roles. The Oran Berry heals 100 HP (rather than 10 HP in the core series), while the Sitrus Berry heals all HP (rather than only 30 HP or ¼ of the Pokémon's total HP in the core series).
 * Sitrus Berries can also increase the player's total HP by 2 points if consumed at full health.
 * In Super Pokémon Mystery Dungeon eating an Oran Berry will increase maximum HP by 10 for the current adventure only if the Pokémon consuming the item has a maximum HP of less than 100, or is on full health.

The element of hunger and IQ led to the adoption of the concepts of and Gummis, respectively. The only human-made items present that are also present in the core series games are Max Elixirs and TMs. Other items include Wonder Orbs and Scarves, the latter were removed and somewhat replaced by Looplets in Super Pokémon Mystery Dungeon.

In addition, any Pokémon can hold any item.

Throwing items
Much like in the Safari Zone of the core series games, where the player is able to toss Bait or throw a Rock (or Mud) at Pokémon, throwing items in Mystery Dungeon deals damage. The player is able to stock up to 99 units of a throwing item in a single item space in contrast to other items, where multiple items take up multiple spaces in the item list.
 * This does not apply to Unown Stones.
 * Wands were an item introduced in Super Pokémon Mystery Dungeon. They behave similarly to Throwing items though can only be stacked up to 40 and whilst some deal damage, they have varying affects such as Warping the target or causing various Status Conditions.

Looplets and Emeras
In Pokémon Super Mystery Dungeon, a new class of held items were introduced. Looplets are items to be held by a Pokémon which can boost certain stats, protect from status and weather, or other effects. In addition, each Looplet has a certain number of slots to equip Emeras onto. Emeras are items which can be found scattered around dungeons. They can be used to temporarily boost a particular stat for the duration of the dungeon, or equipped onto a Looplet for various effects. Emera effects can include boosting attack power, adding a chance to inflict status effects, or allowing the user to see all enemy Pokémon or items on the floor. All effects and stat boosts from Emeras disappear upon leaving the dungeon.

Meccaniche di gioco di Pokémon Mystery Dungeon