Evolution

Ash's Sandile evolving in the anime

Evolution, in the Pokémon franchise, is when one Pokémon, upon reaching a certain level, using a certain stone, learning a certain move, or being traded, evolves into a different kind of Pokémon. In Pokémon Gold, Silver, Crystal, HeartGold and SoulSilver games, it says that Professor Elm is an expert on evolution and discovered that Pikachu evolves from  Pichu.

Normal Evolution Tricks

Pokémon gain experience after battling wild Pokémon and Pokémon Trainers. The more experience a Pokémon gains, the more it levels up. When a Pokémon reaches a particular level, it will evolve into its next form, if it has one. This is very helpful to most Trainers who want their Pokémon to become stronger.

There are ways to share experience, such as allow a Pokémon you wish it to evolve to hold Exp. Share. It is a hold item that allows the user to earn experience even if it did not participate in the battle. This is a convenient tool if you want to level up a new or low-level Pokémon.

You can prevent evolution by simply press the 'B' button on the Game when the Pokémon is attempting to evolve. This is useful as some Pokémon will learn moves that cannot be learnt in a later form or if you want a Pokémon to learn a move earlier than usual. For example, Gabite. If you let Gible evolve into Gabite at level 24 it will learn Dragon Rush at level 49, but if you keep Gible it will learn Dragon Rush at level 37. Sometimes it doesn't matter if you let it evolve or not. The Pokémon can hold an Everstone, which keeps them from evolving, so that you don't have to keep cancelling the evolution everytime the Pokémon levels up. However, if your Pokémon has evolved, it might not evolve again (Raticate, Linoone, etc.) Although some Pokémon can evolve more than once (Poliwhirl, Cascoon, etc.), some basic Pokémon just can't evolve, due to undiscovered forms, or if they are really rare (Chatot, Groudon, etc.) There are also Pokémon that can evolve into different things like love, choice, etc. For example, Eevee, Poliwhirl, Wurmple, or Kirlia.

Special Condition Evolutions

Stone Evolutions

Some Pokémon will not evolve unless you use a special stone called an Evolution Stone. These special Items are linked to the Pokémon's type. Here are a list of Pokémon that can evolve by giving them the stones.

List of Pokémon that Evolve by Evolution Stones
Name	Conditions	Evolve to
Vulpix	Fire Stone	Ninetales
Growlithe		Arcanine
Eevee		Flareon
Pansear		Simisear
Pikachu	Thunderstone	Raichu
Eevee		Jolteon
Eelektrik		Eelektross
Poliwhirl	Water Stone	Poliwrath
Shellder		Cloyster
Staryu		Starmie
Eevee		Vaporeon
Lombre		Ludicolo
Panpour		Simipour
Gloom	Leaf Stone	Vileplume
Weepinbell		Victreebel
Exeggcute		Exeggutor
Nuzleaf		Shiftry
Pansage		Simisage
Gloom	Sun Stone	Bellossom
Sunkern		Sunflora
Cottonee		Whimsicott
Petilil		Lilligant
Helioptile		Heliolisk
Nidorina	Moon Stone	Nidoqueen
Nidorino		Nidoking
Clefairy		Clefable
Jigglypuff		Wigglytuff
Skitty		Delcatty
Munna		Musharna
Roselia	Shiny Stone	Roserade
Togetic		Togekiss
Minccino		Cinccino
Floette		Florges
Kirlia (♂ - Male)	Dawn Stone	Gallade
Snorunt (♀ - Female)		Froslass
Murkrow	Dusk Stone	Honchkrow
Misdreavus		Mismagius
Lampent		Chandelure
Doublade		Aegislash

Item Evolutions

Some items are needed for a Pokémon to evolve. If a Pokémon hold the item allowing it to evolve, let it level up once and it will then evolve into the second form.

List of Pokémon that Evolve by Attached Items
Name	Conditions	Evolve to
Gligar	Held Item: Razor Fang at Night	Gliscor
Sneasel	Held Item: Razor Claw at Night	Weavile
Happiny	Held Item: Oval Stone at Day	Chansey

Trading Evolutions

A small group of Pokémon refuses to evolve, no matter if you are at the appropriate level to trigger the evolve process, unless you trade them with a friend. Some Pokémon need to have a held item to evolve when trading with a friend. Another group require specific Pokémon to be trade in order to evolve.

List of Pokémon that Evolve by Trading
Name	Conditions	Evolve to
Kadabra	None	Alakazam
Haunter		Gengar
Machoke		Machamp
Graveler		Golem
Boldore		Gigalith
Gurdurr		Conkeldurr
Phantump		Trevenant
Pumpkaboo		Gourgeist
Onix	Held Item: Metal Coat	Steelix
Scyther		Scizor
Poliwhirl	Held Item: King's Rock	Politoed
Slowpoke		Slowking
Seadra	Held Item: Dragon Scale	Kingdra
Porygon	Held Item: Up-Grade	Porygon2
Clamperl	Held Item: Deepseascale	Gorebyss
Clamperl	Held Item: Deepseatooth	Huntail
Electabuzz	Held Item: Electrizer	Electivire
Magmar	Held Item: Magmarizer	Magmortar
Rhydon	Held Item: Protector	Rhyperior
Porygon2	Held Item: Dubious Disc	Porygon-Z
Feebas	Held Item: Prism Scale (Generation V-)	Milotic
Dusclops	Held Item: Reaper Cloth	Dusknoir
Shelmet	Trade with Karrablast	Accelgor
Karrablast	Trade with Shelmet	Escavalier
Spritzee	Held Item: Sachet	Aromatisse
Swirlix	Held Item: Whipped Dream	Slurpuff

Gender Evolution

Small groups of Pokémon requires a gender to evolve into the next stage.

List of Pokémon that Evolve by Gender
Name	Conditions	Evolve to
Burmy File:412C.png	Level 20, (♀ - Female)	Wormadam File:413C.png
	Level 20, (♂ - Male)	Mothim
Combee	Level 25, (♀ - Female)	Vespiquen

Friendship Evolutions

Certain Pokémon, especially baby Pokémon, requires friendship with its trainer and if they are fond enough, they are willing to evolve. Some Pokémon only evolves in a certain time of the day with friendship.

List of Pokémon that Evolve by Friendship
Name	Conditions	Evolve to
Golbat	None	Crobat
Chansey		Blissey
Pichu		Pikachu
Cleffa		Clefairy
Igglybuff		Jigglypuff
Togepi		Togetic
Azurill		Marill
Buneary		Lopunny
Munchlax		Snorlax
Woobat		Swoobat
Swadloon		Leavanny
Eevee	at Day	Espeon
Budew		Roselia
Riolu		Lucario
Eevee	at Night	Umbreon
Chingling		Chimecho

Location Based Evolutions

Special Pokémon evolve at a certain area of location.

List of Pokémon that Evolve by Locations
Name	Locations	Evolve to
Magneton	Mt. Coronet (Generation IV), Chargestone Cave (Generation V), Route 13 (Generatiion VI)	Magnezone
Nosepass		Probopass
Eevee	Moss Rock at Eterna Forest (Generation IV), Moss Rock at Pinwheel Forest (Generation V), Route 20 (Generation VI)	Leafeon
Eevee	Ice Rock at Route 217 (Generation IV), Ice Rock at Twist Mountain (Generation V), Frost Cave (Generation VI)	Glaceon

Attack Based Evolutions

Certain Pokémon need to know a move to evolve. This method was introduced in Generation IV, starting with Diamond/Pearl/Platinum.

List of Pokémon that Evolve by Learning Moves
Name	Conditions	Evolve to
Tangela	learning AncientPower	Tangrowth
Yanma		Yanmega
Piloswine		Mamoswine
Bonsly	learning Mimic	Sudowoodo
Mime Jr.		Mr. Mime
Lickitung	learning Rollout	Lickilicky
Aipom	learning Double Hit	Ambipom

Unique Evolutions

Some Pokémon have certain type of unique way of evolve.

List of Pokémon that Evolve by Unique Way
Name	Conditions	Evolve to
Eevee	2+ Affection in Pokémon-Amie, learn a -type move.	Sylveon
Wurmple	Level 7 (Random depending on PV - Personality Value)	Silcoon
		Cascoon
Tyrogue	Level 20, Attack stats more than Defense	Hitmonlee
	Level 20, Defense stats more than Attack	Hitmonchan
	Level 20, Attack stats equal to Defense	Hitmontop
Feebas	Maxed out Beauty Condition and then level up (Generation III - IV)	Milotic
Nincada	Level 20, with empty Poké Ball and an open slot on your party.	Shedinja
Mantyke	A Remoraid in your party and then level up.	Mantine
Pancham	Level 32+ with a -type in your party.	Pangoro
Inkay	Level 30+ while holding the Nintendo 3DS upside down.	Malamar
Tyrunt	Level 39+ during the day.	Tyrantrum
Amaura	Level 39+ during the night.	Aurorus
Sliggoo	Level 50+ in the rain.	Goodra

Mega Stone Evolutions

Certain Pokémon will be able to evolve into a Mega form, the final form for one-evolution families and second/true final form for two-evolution families with the use of a Mega Stone, a held object. However this evolution will devolve back into their previous form at the end of the battle.

List of Pokémon Mega Evolve
Name	Conditions	Evolve to
Venusaur	Hold Venusaurite	Mega Venusaur
Charizard	Hold Charizardite X or Y	Mega Charizard X
		Mega Charizard Y
Blastoise	Hold Blastoisite	Mega Blastoise
Alakazam	Hold Alakazamite	Mega Alakazam
Gengar	Hold Gengarite	Mega Gengar
Kangaskhan	Hold Kangaskhanite	Mega Kangaskhan
Pinsir	Hold Pinsirite	Mega Pinsir
Gyarados	Hold Gyaradosite	Mega Gyarados
Aerodactyl	Hold Aerodactylite	Mega Aerodactyl
Mewtwo	Hold Mewtwonite X or Y	Mega Mewtwo X
		Mega Mewtwo Y
Ampharos	Hold Ampharosite	Mega Ampharos
Scizor	Hold Scizorite	Mega Scizor
Heracross	Hold Heracronite	Mega Heracross
Houndoom	Hold Houndoomite	Mega Houndoom
Tyranitar	Hold Tyranitarite	Mega Tyranitar
Blaziken	Hold Blazikenite	Mega Blaziken
Gardevoir	Hold Gardevoirite	Mega Gardevoir add mega mawile
Aggron	Hold Aggronite	Mega Aggron
Medicham	Hold Medichamite	Mega Medicham
Manectric	Hold Manectite	Mega Manectric
Banette	Hold Banettite	Mega Banette
Absol	Hold Absolite	Mega Absol
Garchomp	Hold Garchompite	Mega Garchomp
Lucario	Hold Lucarionite	Mega Lucario
Abomasnow	Hold Abomanite	Mega Abomasnow

Devolution

Devolution is a form of reverse evolution when a Pokemon reverts to a previous state. Devolution does not exist in the games but is common in the Manga and TCG. Devolution is achieved mainly unnaturaly - through experimentation, or Devolution Spray. Though certain Pokemon, such as Isamu's Clefairy and Pikachu are capable of devolving themselves. The TCG also has it that Eeveelutions can revert into Eevee and that Mew has two special attacks named the Devolution Beam and Devo Crush - both of which which devolves the Pokemon hit by the attack. Golurk and Jirachi also possess special attacks which allow them to devolve an opposing Pokemon.

Trivia

There are eight pokémon that can evolve into two different pokémon, but only two that evolve into more: Tyrogue and Eevee.

Notes

• As of Generation VI, there are sixty Pokémon that do not evolve in anyway. This is discounting Mega Evolution, and the Fifty-one Legendary Pokémon.