Glossary
60 mechanics terms, dated to the generation that introduced them
One sentence per term here; each page adds the detail, later changes and the guides that use the term.
Main-series games only, read 8 Nov 2026.
Generation I introduced 32 terms
- Gen IBase stat totalThe sum of a species' six base stats, used as a rough measure of overall strength.
- Gen IBase statsThe six numbers fixed per species that set how high each of its stats can grow.
- Gen ICatch rateA species value from 3 to 255 that sets how easily it can be caught.
- Gen ICritical hitA random hit that deals extra damage and ignores some stat changes.
- Gen IDamage rollThe random factor applied to each damaging hit, so the same move can deal a range of damage.
- Gen IEffort values (EVs)Points a Pokémon earns from the species it defeats, raising specific stats.
- Gen IEvolutionA permanent change from one species to another, triggered by a condition such as a level, an item or a trade.
- Gen IGenerationA grouping of the main-series games released between one set of new species and the next.
- Gen IGrowth rateThe experience curve a species follows, which sets how many points it needs for each level.
- Gen IHidden Machine (HM)A reusable item that taught a move also needed to cross obstacles in the overworld.
- Gen IImmunityA 0 times entry in the type chart, or an ability or rule that blocks a move or effect entirely.
- Gen IIndividual values (IVs)Hidden per-individual numbers that add to each stat and make two members of a species differ.
- Gen ILearnsetThe full list of moves a species can learn in one game, by level-up, TM, tutor or egg.
- Gen ILegendary PokémonA group of rare species, usually one per save file, that sit in the Undiscovered egg group and carry high base stats.
- Gen ILevelA number from 1 to 100 that scales every stat and gates level-up moves and evolutions.
- Gen INational Pokédex numberThe fixed number each species holds across every game, from 1 for Bulbasaur onward.
- Gen IPoké BallThe handheld capture device thrown at a wild Pokémon; the item family includes many types with different catch modifiers.
- Gen IPower points (PP)The number of times a move can be used before the Pokémon rests or uses an item.
- Gen IPriorityA move property from +5 to -7 that decides turn order before Speed is compared.
- Gen ISpecialThe single stat that covered both special offense and special defense in Generation I.
- Gen ISpeedThe stat that orders actions within a priority bracket; the faster Pokémon moves first.
- Gen ISTAB (same-type attack bonus)A 1.5 times damage bonus when a Pokémon uses a move that matches one of its own types.
- Gen IStatOne of the six battle values: HP, Attack, Defense, Special Attack, Special Defense and Speed.
- Gen IStat stagesTemporary in-battle modifiers from -6 to +6 applied to a stat by moves and abilities.
- Gen IStatus conditionA lasting affliction such as burn, freeze, paralysis, poison or sleep that stays after switching.
- Gen ITechnical Machine (TM)An item that teaches a move to any compatible Pokémon.
- Gen ITrade evolutionAn evolution that happens when a Pokémon is traded to another game, sometimes while holding an item.
- Gen ITypeAn elemental label on each species and each move that sets damage multipliers through the type chart.
- Gen IType chartThe table of damage multipliers for every attacking type against every defending type.
- Gen IType effectivenessThe multiplier a move's type receives against the target's types: 0, 0.25, 0.5, 1, 2 or 4 times.
- Gen IVersion exclusiveA species or item that appears in only one game of a paired release.
- Gen IVersion groupA set of games that share one set of learnsets and game data, used to key every move list on this site.
Generation II introduced 14 terms
- Gen IIAlternate formA variant of one species with a different appearance, and sometimes different types, stats or ability.
- Gen IIBreedingLeaving two compatible Pokémon at a Day Care or Nursery to produce an egg.
- Gen IIEggThe item a breeding pair produces, which hatches into a level 1 Pokémon after a set amount of walking.
- Gen IIEgg groupA breeding category; two Pokémon can produce an egg only if they share an egg group or one is Ditto.
- Gen IIEgg moveA move a Pokémon can know only by hatching from an egg with a parent that knows it.
- Gen IIEntry hazardA field effect on one side that damages or affects each Pokémon that switches in.
- Gen IIFriendshipA hidden value from 0 to 255 that rises with care and battling and powers certain evolutions and moves.
- Gen IIGenderMale, female or genderless, set per individual from a species-wide ratio.
- Gen IIHeld itemAn item a Pokémon carries into battle for a passive or triggered effect.
- Gen IIMove tutorA non-player character who teaches a move, often for a fee or an item.
- Gen IIPokérusA rare, harmless virus that doubles the effort values a Pokémon earns while infected.
- Gen IIRegional PokédexThe numbered list of species found in one game's region, separate from the national order.
- Gen IIShinyA rare alternate colouration of an individual Pokémon, with no effect on its stats in current games.
- Gen IIWeatherA battlefield condition that changes move power, accuracy and some damage for several turns.
Generation III introduced 3 terms
- Gen IIIAbilityA passive effect each Pokémon carries in battle, drawn from its species' list of one or two standard abilities.
- Gen IIIDouble battleA battle format with two active Pokémon on each side at once.
- Gen IIINatureA per-individual trait that raises one stat by 10 percent and lowers another by 10 percent.
Generation IV introduced 2 terms
- Gen IVMasuda methodBreeding two Pokémon from games of different languages, which raises the egg's chance of being shiny.
- Gen IVPhysical and special splitThe rule, from Generation IV, that each damaging move is physical or special on its own rather than by its type.
Generation V introduced one term
- Gen VHidden abilityA species' third possible ability, obtained only through specific encounters, items or breeding.
Generation VI introduced 2 terms
- Gen VIMega EvolutionA once-per-battle transformation, triggered by a held Mega Stone, that raises base stats by 100 and can change type and ability.
- Gen VITerrainA five-turn field effect that changes moves and status for Pokémon on the ground.
Generation VII introduced 3 terms
- Gen VIIHyper TrainingA service that treats a Pokémon's chosen IVs as 31 for stat calculation in exchange for Bottle Caps.
- Gen VIIRegional formA variant of an existing species, native to one region, with a different appearance and often a different type and stats.
- Gen VIIZ-MoveA once-per-battle move of raised power, unlocked by a held Z-Crystal in Sun and Moon.
Generation VIII introduced 2 terms
- Gen VIIIDynamaxA three-turn battle state in Sword and Shield that enlarges a Pokémon, raises its HP and turns its moves into Max Moves.
- Gen VIIIGigantamaxA Dynamax variant with a distinct form and a signature G-Max Move, available to specific species.
Generation IX introduced one term
- Gen IXTerastallizationA once-per-battle change that replaces a Pokémon's defensive types with its single Tera Type.