User:Force Fire/Sandbox

What a Pokémon gains is listed in generational order
List is only counting what the specific Pokémon (and at the time pre-evolutions - if any) gains, not what its future evolution or forms gain (that is, Steelix getting a Mega Evolution counts for Steelix, not Onix)
- Regional evolutions of regional forms are an exception as the latter are considered the same species as the original (that is, Kantonian Meowth and Galarian Meowth are both "Meowth", therefore Perresrker counts as Kantonian Meowth gaining something)
Forms gained within the same generation do not count (that is, Giratina getting the Origin forme does not count as it gained it in its introductory generation, whereas Dialga and Palkia getting Origin formes would count as they gained them in a later generation)
Convergent and Paradox Pokémon are not counted as they are separate species (that is, Tentacool does not evolve into Toedscruel and Magneton does not evolve into Sandy Shocks or transform into it via a Mega Stone-like item)

Generation I

Pokémon	Gains
Venusaur	Mega Evolution, Gigantamax form
Charizard	Mega Evolution, Gigantamax form
Blastoise	Mega Evolution, Gigantamax form
Butterfree	Gigantamax form
Beedrill	Mega Evolution
Pidgeot	Mega Evolution
Raticate	Regional form (Alola)
Fearow	N/A
Arbok	N/A
Raichu	Baby (Pichu), Regional form (Alola), Gigantamax form (Pikachu only), Mega Evolution
Sandslash	Regional form (Alola)
Nidoqueen	N/A
Nidoking	N/A
Clefable	Baby (Cleffa), Type change (Fairy), Mega Evolution
Ninetales	Regional form (Alola)
Wigglytuff	Baby (Igglybuff), Type change (Fairy)
Golbat	Evolution (Crobat)
Vileplume	Alternate evolution (Bellossom)
Parasect	N/A
Venomoth	N/A
Dugtrio	Regional form (Alola)
Persian	Regional form (Alola), Regional form (Galar - Meowth only), Regional evolution (Perrserker)
Golduck	N/A
Primeape	Evolution (Annihilape)
Arcanine	Regional form (Hisui)
Poliwrath	Alternate evolution (Politoed)
Alakazam	Mega Evolution
Machamp	Gigantamax form
Victreebel	Mega Evolution
Tentacruel	N/A
Golem	Regional form (Alola)
Rapidash	Regional form (Galar)
Slowbro	Alternate evolution (Slowking), Mega Evolution, Regional form (Galar)
Magneton	Type change (Steel), Evolution (Magnezone)
Farfetch'd	Regional form (Galar), Regional evolution (Sirfetch'd)
Dodrio	N/A
Dewgong	N/A
Muk	Regional form (Alola)
Cloyster	N/A
Gengar	Mega Evolution, Gigantamax form
Onix	Evolution (Steelix)
Hypno	N/A
Kingler	Gigantamax form
Electrode	Regional form (Hisui)
Exeggutor	Regional form (Alola)
Marowak	Regional form (Alola)
Hitmonlee	Baby (Tyrogue), Alternate evolution (Hitmontop)
Hitmonchan	Baby (Tyrogue), Alternate evolution (Hitmontop)
Lickitung	Evolution (Lickilicky)
Weezing	Regional form (Galar)
Rhydon	Evolution (Rhyperior)
Chansey	Evolution (Blissey), Baby (Happiny)
Tangela	Evolution (Tangrowth)
Kangaskhan	Mega Evolution
Seadra	Evolution (Kingdra)
Seaking	N/A
Starmie	Mega Evolution
Mr. Mime	Baby (Mime Jr.), Type change (Fairy), Regional form (Galar), Regional evolution (Mr. Rime)
Scyther	Evolution (Scizor, Kleavor)
Jynx	Baby (Smoochum)
Electabuzz	Baby (Elekid), Evolution (Electivire)
Magmar	Baby (Magby), Evolution (Magmortar)
Pinsir	Mega Evolution
Tauros	Regional form (Paldea)
Gyarados	Mega Evolution
Lapras	Gigantamax form
Ditto	N/A
Vaporeon	Alternate evolution (Espeon, Umbreon, Leafeon, Glaceon, Sylveon), Gigantamax form (Eevee only)
Jolteon	Alternate evolution (Espeon, Umbreon, Leafeon, Glaceon, Sylveon), Gigantamax form (Eevee only)
Flareon	Alternate evolution (Espeon, Umbreon, Leafeon, Glaceon, Sylveon), Gigantamax form (Eevee only)
Porygon	Evolution (Porygon2)
Omastar	N/A
Kabutops	N/A
Aerodactyl	Mega Evolution
Snorlax	Baby (Munchlax), Gigantamax form
Articuno	Regional form (Galar)
Zapdos	Regional form (Galar)
Moltres	Regional form (Galar)
Dragonite	Mega Evolution
Mewtwo	Mega Evolution
Mew	N/A

Generation II

Pokémon	Gains
Meganium	Mega Evolution
Typhlosion	Regional form (Hisui)
Feraligatr	Mega Evolution
Furret	N/A
Noctowl	N/A
Ledian	N/A
Ariados	N/A
Crobat	Evolution of pre-existing Pokémon (Golbat)
Lanturn	N/A
Pichu	Baby of a pre-existing Pokémon (Pikachu)
Cleffa	Baby of a pre-existing Pokémon (Clefairy), Type change (Fairy)
Igglybuff	Baby of a pre-existing Pokémon (Jigglypuff), Type change (Fairy)
Togetic	Evolution (Togekiss), Type change (Fairy)
Xatu	N/A
Ampharos	Mega Evolution
Bellossom	Alternate evolution of a pre-existing Pokémon (Gloom)
Azumarill	Baby (Azurill), Type change (Fairy)
Sudowoodo	Baby (Bonsly)
Politoed	Alternate evolution of a pre-existing Pokémon (Poliwhirl)
Jumpluff	N/A
Aipom	Evolution (Ambipom)
Sunflora	N/A
Yanma	Evolution (Yanmega)
Quagsire	Regional form (Paldea), Regional evolution (Clodsire)
Espeon	Alternate evolution of a pre-existing Pokémon (Eevee)
Umbreon	Alternate evolution of a pre-existing Pokémon (Eevee)
Murkrow	Evolution (Honchkrow)
Slowking	Alternate evolution of a pre-existing Pokémon (Slowpoke), Regional form (Galar)
Misdreavus	Evolution (Mismagius)
Unown	Forms (!, ?)
Wobbuffet	Baby (Wynaut)
Girafarig	Evolution (Farigiraf)
Forretress	N/A
Dunsparce	Evolution (Dudunsparce)
Gligar	Evolution (Gliscor)
Steelix	Evolution of a pre-existing Pokémon (Onix), Mega Evolution
Granbull	Type change (Fairy)
Qwilfish	Regional form (Hisui), Regional evolution (Overqwil)
Scizor	Evolution of a pre-existing Pokémon (Scyther), Mega Evolution
Shuckle	N/A
Heracross	Mega Evolution
Sneasel	Evolution (Weavile), Regional form (Hisui), Regional evolution (Sneasler)
Ursaring	Evolution (Ursaluna)
Magcargo	N/A
Piloswine	Evolution (Mamoswine)
Corsola	Regional form (Galar), Regional evolution (Cursola)
Octillery	N/A
Delibird	N/A
Mantine	Baby (Mantyke)
Skarmory	Mega Evolution
Houndoom	Mega Evolution
Kingdra	Evolution of a pre-existing Pokémon (Seadra)
Donphan	N/A
Porygon2	Evolution of a pre-existing Pokémon (Porygon), Evolution (Porygon-Z)
Stantler	Evolution (Wyrdeer)
Smeargle	N/A
Tyrogue	Baby of a pre-existing Pokémon (Hitmonlee, Hitmonchan)
Hitmontop	Alternate evolution of a pre-existing Pokémon (Hitmonlee, Hitmonchan)
Smoochum	Baby of a pre-existing Pokémon (Jynx)
Elekid	Baby of a pre-existing Pokémon (Electabuzz)
Magby	Baby of a pre-existing Pokémon (Magmar)
Miltank	N/A
Blissey	Evolution of a pre-existing Pokémon (Chansey)
Raikou	N/A
Entei	N/A
Suicune	N/A
Tyranitar	Mega Evolution
Lugia	N/A
Ho-Oh	N/A
Celebi	N/A

Generation III

Pokémon	Gains
Sceptile	Mega Evolution
Blaziken	Mega Evolution
Swampert	Mega Evolution
Glalie	Alternate evolution (Froslass)

Generation IV

Pokémon	Gains
Torterra	N/A
Infernape	N/A
Empoleon	N/A
Froslass	Alternate evolution of a pre-existing Pokémon (Snorunt), Mega Evolution

Generation V

Pokémon	Gains
Victini	N/A
Serperior	N/A
Emboar	Mega Evolution
Samurott	Regional form (Hisui)
Excadrill	Mega Evolution
Scolipede	Mega Evolution
Scrafty	Mega Evolution
Eelektross	Mega Evolution
Chandelure	Mega Evolution

Generation VI

Pokémon	Gains
Chesnaught	Mega Evolution
Delphox	Mega Evolution
Greninja	Mega Evolution
Pyroar	Mega Evolution
Floette	Mega Evolution (Eternal Floette only)
Malamar	Mega Evolution
Barbaracle	Mega Evolution
Dragalge	Mega Evolution
Hawlucha	Mega Evolution
Zygarde	Mega Evolution