In the Pokémon Mystery Dungeon series, the regular attack is a typeless attack of very low power that is used by pressing "A" to attack while inside a dungeon. In these games, all Pokémon have this standard regular attack in addition to their moves. The use of the regular attack is highly discouraged among many strategy guides due to its minimal impact, and even by the games themselves, as using regular attacks to defeat an opponent is ineffective and affects the number of Experience Points rewarded to the player's exploration team.
Any time a Pokémon runs out of PP, its only remaining options for attacking are to use its regular attack, or to use Struggle.
Pokémon Mystery Dungeon: Explorers of Time and Pokémon Mystery Dungeon: Explorers of Darkness and Pokémon Mystery Dungeon: Explorers of Sky[]
In the Explorers games, defeating an enemy Pokémon with only the repeated usage of the regular attack, and no moves, halves the number of experience points that the player's team earns. For example, an enemy Pokémon that would normally earn you 60 experience points instead earns you only 30 experience points if you defeated it using only the regular attack. Only one move needs to be used on the enemy by at least one member of the player's team. If the team leader, partner, or an ally uses an attacking move and does not knock out the enemy, and then repeatedly strikes the enemy with the regular attack until the enemy is defeated, the player's team still earns the full number of experience points. At least one move has to have hit the enemy; if a move misses, or if the move failed due to an ability (such as using Earthquake on a Pokémon with Levitate, or using Thunderbolt on the same floor as a Pokémon with Lightning Rod), the move does not count toward the "at least one move" requirement.
The benefit of using moves versus using the regular attack is the subject of the fifth diary entry in Bidoof's diary at Wigglytuff's Guild, titled "Moves Are Awesome!" This benefit is also explicitly mentioned in the tutorial-style tips during the player's first visit to Drenched Bluff in Chapter 2.
In most post-credits dungeons, starting with Mystifying Forest, high-leveled Pokémon, typically Level 30–50, appear as enemies in the dungeons alongside low-leveled Pokémon, typically Level 5–15, but in some cases, being as low as Level 1. The official strategy guide book Pokémon Mystery Dungeon: Explorers of Time, Explorers of Darkness: Prima Official Game Guide mentions this on its page for Mystifying Forest, recommending the player to use moves on the high-leveled Pokémon and regular attacks on the low-leveled ones. Players typically have Pokémon in the Level 40-50 range at that point, and low-leveled enemies are easily defeated by a single regular attack from Pokémon of that level range.
Any Pokémon with Wonder Guard takes only 1 HP of damage from the regular attack, regardless of attacking or defending stats. Unlike in the core series, enemy Shedinja (found at Mt. Travail) has 10 HP in this game. While Shedinja is the only Pokémon that has this ability naturally, other Pokémon can get it through Trace. If the player recruits a Shedinja, the Shedinja's HP stat has no special limit; it caps at 999 HP just like any other Pokémon in this game.
The regular attack is typeless, unless used by a Pokémon with Normalize, in which case it deals Normal-type damage.
There is no limit to the amount of damage that can be dealt with a regular attack.
Pokémon Mystery Dungeon: Gates to Infinity[]
In Gates to Infinity, the regular attack was nerfed to do at most 5 HP of damage, no matter how high the user's attacking stat is, and no matter how low the target's defending stat is, unlike in the Explorers games, where regular attack damage was not limited.