Methods of evolution
|
This article does not yet meet the quality standards of Bulbapedia. Please feel free to edit this article to make it conform to Bulbapedia norms and conventions. |
There are numerous methods of evolution, which define how and when Pokémon evolve. Most Pokémon will evolve by leveling up while others evolve through specific means, such as being traded, achieving maximum happiness, or leveling at certain times, among others.
Triggers
Across all generations, Pokémon may only evolve after one of three events:
Though these three are the activating events for evolution, there is always a catalyst required for the evolution to begin. If the catalyst is present and the evolutionary event is activated, the Pokémon will evolve at the end of the process that caused the activating event (at the end of a battle or after a trade has been completed). An Everstone held by the Pokémon can stop this in any event.
Leveling up
Most Pokémon that evolve do so after leveling up. This can be triggered by gaining experience in battle or by using a Rare Candy. Several additional conditions must be met in addition to gaining a level for a Pokémon to evolve, such as being at or above a specific level, knowing a move, or being in a specific place. It should be noted that a Pokémon left in the Daycare will not evolve, even if other conditions are met. When these conditions are met, a Pokémon will attempt to evolve every time it gains a level unless the conditions are removed.
At or above a certain level
Most Pokémon, with at least one in nearly every evolution family, will evolve when they reach or surpass a certain level. A Pokémon that levels up to this level or a higher level will attempt to evolve every time it does so, at the end of the battle in which it attained this level or after a Rare Candy has been used.
As there are so many Pokémon that use this method of evolution, any Pokémon that evolve that are not listed here are those which undergo evolution based upon their current level.
When happiness is high
Some Pokémon will only evolve when their happiness reaches 220 or above and they are leveled up. This is most common with baby Pokémon, however, some others also evolve in this way. Like the happiness system itself, this method of evolution first debuted in Generation II. Like those which evolve when at or above a certain level, a happy Pokémon will attempt to evolve every level until it hits level 100 unless its happiness is reduced.
| Happiness | ||
|---|---|---|
 Buneary |
Happiness → |  Lopunny |
When the Pokémon knows a certain move
Some Pokémon evolve only if they currently known a certain move and are then leveled up. These moves are commonly available by leveling up (in which case the Pokémon will evolve at the end of the battle in which it learned the move), though some must be taught via move relearner. This method was introduced in Generation IV.
| Knowing a move | ||
|---|---|---|
 Tangela |
→ Level up knowing AncientPower |
 Tangrowth |
When trained in a certain area
Pokémon can evolve based upon their environment. Several evolutions introduced in Generation IV take advantage of this.
| Leveling up somewhere | ||
|---|---|---|
 Nosepass |
→ Level up in Mt. Coronet |
 Probopass |
When holding an item
Several Pokémon evolve if they level up while holding a specific evolution-inducing held item. When this occurs, the item disappears upon completion of the evolution.
| Leveling up somewhere | ||
|---|---|---|
 Sneasel |
→ Level up holding Razor Claw (Night) |
 Weavile |
At certain times
The current time will sometimes affect evolution, but it is never the sole catalyst; it always is used in tandem with another (currently, happiness and a held item are the only ones it is paired with).
| Leveling up somewhere | ||
|---|---|---|
Sneasel |
→ Level up holding Razor Claw (Night) |
Weavile |
Unique conditions
The following Pokémon evolve through a method that is isolated to their evolution line only.
- Mantyke evolves into Mantine when it levels up only if there is a Remoraid in user's party.
- Feebas evolves into Milotic by leveling up if its Beauty stat is 170 or above.
- Combee evolves into a Vespiquen at level 21 if it is female. Male Combee do not evolve.
- When Nincada evolves into Ninjask (at level 20), if there is an empty slot in the party, a Shedinja will appear. In Generation IV, the player must also have a spare Poké Ball in their bag.
Additional factors
Some Pokémon from branched evolution families evolve into different forms depending on some additional factors. These factors are not conditions for evolution, since they do not determine the possibility of evolution, but what the Pokémon will become after evolution.
- Burmy. This Pokémon evolves at level 20, but its new form is determined by its gender and cloak (and cloak changes according to the place, where it has battled last time).
- Tyrogue. This Pokémon evolves at level 20 depending on its stats.
- If its Defense is higher than Attack, it evolves into Hitmonchan
- If its Attack is higher than Defense, it evolves into Hitmonlee.
- If Attack is equal to Defense, it evolves into Hitmontop.
- Wurmple. It evolves at level 7 into Silcoon or Cascoon, depending on its personality value. This value is hidden, determined when Pokémon is caught and cannot be affected by the player. See the article about personality value for the exact formula.
For Espeon and Umbreon, see above.
Evolving by evolutionary stone
- Main article: Evolutionary stone
- See also: Pokémon that evolve by evolutionary stone
Some Pokémon evolve when they are exposed to an evolutionary stone. The stone may be applied at any time and causes an instant evolution. The player can decide whether and when to evolve his or her Pokémon, but he or she must choose carefully as most Pokémon will no longer be able to learn certain moves when they evolve in this way, and some (like Raichu and Togekiss) cannot learn any moves by leveling up, although there are exceptions to this rule (see heart scale) and certain moves are exclusive to the stone-evolved Pokémon.
Examples
- Vulpix + Fire Stone → Ninetales
- Poliwhirl + Water Stone → Poliwrath
- Pikachu + Thunder Stone → Raichu
- Weepinbell + Leaf Stone → Victreebel
- Nidorino + Moon Stone → Nidoking
- Gloom + Sun Stone → Bellossom
Usually there are no special requirements for stone-induced evolution, with only two exceptions: Kirlia and Snorunt. They may evolve when they hit a certain level at either gender, or...
| Kirlia | male or female | at level 30 | → Gardevoir |
| male only | + Dawn Stone | → Gallade | |
| Snorunt | male or female | at level 42 | → Glalie |
| female only | + Dawn Stone | → Froslass |
Note that sometimes the Oval Stone is said to be an evolutionary stone, because it is a stone and it is required for an evolution. However, technically Oval Stone is an evolution-inducing held item, which Happiny must be holding to evolve into Chansey when it levels up.
Evolution via trading
- Main article: Trade
- See also: Pokémon that evolve through trading
A select few Pokémon evolve only when they are traded. The evolution starts immediately after the trade is completed, regardless of the method of trading used. However, sometimes there are additional conditions.
Examples:
A well-known mistranslation in the non-Japanese releases of the Generation I games suggested that after trading a man a Raichu, he said that it had evolved. This fueled speculation as to whether or not there would be a third stage to the Pikachu line in Generation II; a third stage was later realized in the form of a Baby Pokémon, Pichu.
Holding a certain item
- Main article: Evolution-inducing held item
- See also: Pokémon that evolve by trading with a held item
Some Pokémon evolve when traded only if they are holding a certain item. Like any evolution-inducing held item, the item disappears after the Pokémon evolves.
Examples
The following Pokémon evolve using this method:
- Slowpoke → Slowking: trade while holding King's Rock
- Onix → Steelix: trade while holding Metal Coat
- Electabuzz → Electivire: trade while holding Electirizer
- Magmar → Magmortar: trade while holding Magmarizer
- Porygon → Porygon2 → Porygon-Z: trade while holding Up-Grade, then trade while holding Dubious Disc
- Clamperl → Huntail: trade while holding DeepSeaTooth
- Clamperl → Gorebyss: trade while holding DeepSeaScale
