General Rules for Attacks
A Pokémon in the ASB is able to use any attack that it can learn through the following methods in the video games:
Mystery Gift Event
XD Purification Moves
This includes any moves learned by preevolutions through these methods, even if they would not normally be able to learn it due to the inability to transfer between Gen I and II and the newer games. In addition, any moves that are usable through error in the games (such as Earthquake Lanturn) or were shown to be usable in the anime but are not normally learnable in the games (such as Whirlwind Bulbasaur) may also be used in the ASB. The official source for the ASB for Level Up, TM/HM, Move Tutor, and Egg Moves is veekun.com; any moves listed there will be considered legal. Additionally, any moves listed in the For Future Reference thread found in the Suggestions & Inquiries subforum are considered legal.
A small number of moves that are considered legal in-game are banned or unusable in the ASB.
Pikachu - Fly, Pain Split (Pichu can use Pain Split, but since Notch Ear Pichu cannot evolve, neither Pikachu nor Raichu have access to the move)
Eevee - Transform
Additional Legal Moves
A small number of basic moves may be ordered for nearly any Pokémon, provided they have sufficient anatomy to perform it.
Tackle, Body Slam, Skull Bash, Headbutt - All Pokémon who are able to achieve a solid form can use these four moves. However, if they cannot use the move legally, Tackle will cause slight recoil, Body Slam will lose its paralysis chance, Skull Bash will lack its protective shield, and Headbutt will be slightly less powerful.
Growl - All Pokémon capable of making vocalizations will be able to use Growl, though Pokémon who are able to use the move legally will be able to perform it more successfully. Bite, Pound, Tail Whip - All Pokémon who have teeth/limbs/a tail may use Bite/Pound/Tail Whip with no reduction in damage or drawbacks.
Agility, Dodge - All Pokémon may be ordered to dodge with Agility, using the short-term version. However, only Pokémon who can legally use the move may use the long-term version, and those who cannot legally learn it will be slightly slower to react. Additionally, all Pokémon may be ordered to dodge, which will involve less energy but will be much less likely to succeed.
Additional Move Rules
Physical and Special Moves - Like in the games, damage-dealing moves fall into two general categories, Physical and Special. However, in the ASB, due to the nature of some moves, there are often instances where the relationship between generating these moves and the type of damage they do or properties they have does not always coincide. Physically generated moves tend to be moves that are performed through physical action, such as direct melee attacks or attacks that involve throwing or propelling objects (such as Rock Slide or Stone Edge). Specially generated moves tend to be moves that are formed from energy or are propelled or altered with energy (such as Water Gun or Ominous Wind). However, there are a number of cases where moves that are specially generated have physical qualities, and some vice versa. Generally, Mud-based moves, Sludge and Acid-based moves, Water moves (not counting moves such as Water Pulse, Bubblebeam or Hidden Power [Water]) and some Wind Moves (see the Wind Moves rules) will break through Light Screen but be stopped by Reflect and be returned by Counter. Additionally, some Physical moves (such as Elemental Punches) will have Special energy elements that will make them slightly more effective against Reflect, though they will not trigger Mirror Coat or be weakened by Light Screen.
Recovery Clause - Any moves considered to be a "recovery move" (i.e. a move that directly restores health) may be used once per Pokémon per battle.
Critical Hits - Random critical hits do not exist in the ASB, but moves may deal more damage than normal under certain circumstances, commonly regarded as a critical hit. Moves such as Crush Claw can cause points that will cause more damage if struck, and moves such as Slash may target weak spots, with a chance of dealing more damage. Additionally, some Pokémon may have vulnerable areas that will result in higher damage if struck.
Draining/Energy Recovery Moves - All draining moves which drain energy and recover it from the foe work similarly, restoring about half the energy drained from the target (unless otherwise stated). Multiple uses of draining moves will cause diminished effects, effecting not only the move used, but other draining moves. However, low-power draining moves such as Leech Life and Absorb are not subject to this. Additionally, any moves that directly recover energy (e.g. Wish, Rest) will suffer from diminishing returns for multiple uses, especially if they are consecutively or within a few rounds.
Sound Moves - There are two kinds of sound moves in the ASB, non-damaging, frequency-based moves and damaging, amplitude-based moves. Non-damaging sound moves (e.g. Supersonic, Screech, Howl, Roar, Noble Roar, etc.) carry no energy themselves and are not subject to any type modification. Pokémon with sensitive hearing are more likely to be startled by these moves and may be more vulnerable to their effects. Damaging sound moves (e.g. Hyper Voice, Boomburst, Round, Chatter, etc.) are simply energy-based moves carried via sound. While those with sensitive hearing will be vulnerable to the associated sound, they will not take additional damage. Type modification will be calculated as normal.
Boosts and Drops - Moves that raise or lower statistics in the ASB function somewhat differently from the games. Most moves raise or lower attack or defense one or more "stages"; each stage corresponds to a roughly 10% increase or decrease in the power of moves or the resistance to attacks. Multiple uses of boosting moves that affect the same stat will cause the boost to be considerably less when over two stages, rising at most to 25%. Boosts will fade over time, taking roughly 3 rounds for a stat to fall or rise from one stage to normal. This means that higher-level stat gains or drops will take longer to fade than lower-level modifications. Non-standard boost/drop moves like Belly Drum or Memento, which drastically change a stat, may not be affected by these rules in the same way. Boost in offensive stats cause increased use in general energy (5% per every 10% increase) but not Type energy, nor do they contribute to short-term exhaustion. Boosts in defensive stats cause a drop in overall speed and movement ability for their duration, but preserve reaction time. Alterations in speed change not only overall movement speed, but also affect reaction time, making it more or less difficult for the affected Pokémon to evade attacks or react to their environment.
Curses - A number of moves in the ASB work by applying strange curses on the foe. These curses act like psuedo-statuses and may trigger boosts from moves like Facade or Hex. While some curses have special rules for their elimination, most will fade after a period of time or if Refresh or Heal Bell is used.
Charm and Related Attacks - Moves like Charm are largely dependent on the mental state of the Pokémon targeted. Although the exact perameter that allows these moves to work varies from move to move, nearly all moves based off Charm are more effective against calmer, less aggressive and fresher foes. Opponets that are enraged, naturally aggressive, tired or have fought for a while against the user will be less vulnerable to their effects.
Attraction - Moves like Attract and Captivate work on body shape, physiology and relative size. Pokémon that are noted to be particularly beautiful may have greater success than others. Reffs discretion should be used; a Skitty may be attractive to a Meowth or a Pikachu and have limited success in attracting a Pidgey or a Machop, but a Wailord will almost certainly be uninterested.
Item Moves - Moves that steal (e.g. Thief, Covet), trade (e.g. Trick, Switcheroo) or dispose of (e.g. Knock Off) items in-game can be used to affect attachable tokens or badges. These moves can only be used once per Pokémon, per move (e.g. a Pokémon can Trick a token on the foe then Knock it Off, but cannot Trick tokens back twice). With the exception of Knock Off, stealing token or item effects last for five rounds before they're returned or the effects wear off. These moves cannot affect Mega Tokens or Badges.
Wind Attacks - Attacks involving wind and air interact with Screens and other similar defensive techniques depending on a variety of factors. Moves that are primarily air-based (generally, Flying-typed wind attacks, such as Razor Wind, Air Cutter or Gust) tend to be fairly "solid", meaning that they will be resisted by Reflect but will break through Light Screen, while energy-based wind attacks (such as Silver Wind, Fairy Wind, Ominous Wind, etc.) will be easily blocked by Light Screen but will break through a Reflect. Ice-based winds fall somewhere between these two categories, being partially absorbed by either screen while still weakening them significantly, due to their blend of forceful wind, energy, and in the case of Blizzard, actual ice. Despite this variability, all wind attacks are boosted by moves that boost Special Attack.