Hail is learned by 21 species by level and 170 by machine

Effect, in PokéAPI's words

“Changes the weather to a hailstorm for five turns.”

Who learns it

170 species in all, 3 of 16 games shown

Brilliant Diamond and Shining Pearl: 117 species

Species	Method	Level
Castform	Level up, Machine	20
Glaceon	Level up, Machine	35
Froslass	Level up, Machine	40
Snorunt	Level up, Machine	45
Glalie	Level up, Machine	47
Spheal	Level up, Machine	48
Articuno	Level up, Machine	50
Seel	Level up, Machine	53
Sealeo	Level up, Machine	58
Walrein	Level up, Machine	64
Dewgong	Level up, Machine	65
Squirtle	Machine
Wartortle	Machine
Blastoise	Machine
Psyduck	Machine
Golduck	Machine
Poliwag	Machine
Poliwhirl	Machine
Poliwrath	Machine
Tentacool	Machine
Tentacruel	Machine
Slowpoke	Machine
Slowbro	Machine
Shellder	Machine
Cloyster	Machine
Krabby	Machine
Kingler	Machine
Chansey	Machine
Kangaskhan	Machine
Horsea	Machine
Seadra	Machine
Goldeen	Machine
Seaking	Machine
Staryu	Machine
Starmie	Machine
Jynx	Machine
Gyarados	Machine
Lapras	Machine
Vaporeon	Machine
Omanyte	Machine
Omastar	Machine
Kabuto	Machine
Kabutops	Machine
Zapdos	Machine
Dratini	Machine
Dragonair	Machine
Dragonite	Machine
Mewtwo	Machine
Mew	Machine
Totodile	Machine
Croconaw	Machine
Feraligatr	Machine
Chinchou	Machine
Lanturn	Machine
Marill	Machine
Azumarill	Machine
Politoed	Machine
Wooper	Machine
Quagsire	Machine
Slowking	Machine
Qwilfish	Machine
Sneasel	Machine
Swinub	Machine
Piloswine	Machine
Corsola	Machine
Delibird	Machine
Mantine	Machine
Kingdra	Machine
Smoochum	Machine
Blissey	Machine
Suicune	Machine
Lugia	Machine
Mudkip	Machine
Marshtomp	Machine
Swampert	Machine
Lotad	Machine
Lombre	Machine
Ludicolo	Machine
Wingull	Machine
Pelipper	Machine
Azurill	Machine
Carvanha	Machine
Sharpedo	Machine
Wailmer	Machine
Wailord	Machine
Lunatone	Machine
Barboach	Machine
Whiscash	Machine
Corphish	Machine
Crawdaunt	Machine
Feebas	Machine
Milotic	Machine
Absol	Machine
Clamperl	Machine
Huntail	Machine
Gorebyss	Machine
Relicanth	Machine
Luvdisc	Machine
Regice	Machine
Kyogre	Machine
Piplup	Machine
Prinplup	Machine
Empoleon	Machine
Buizel	Machine
Floatzel	Machine
Shellos	Machine
Gastrodon	Machine
Happiny	Machine
Finneon	Machine
Lumineon	Machine
Mantyke	Machine
Snover	Machine
Abomasnow	Machine
Weavile	Machine
Mamoswine	Machine
Palkia	Machine
Manaphy	Machine

Sword and Shield: 141 species

Species	Method	Level
Vanillite	Level up, Machine	20
Vanillish	Level up, Machine	20
Vanilluxe	Level up, Machine	20
Frosmoth	Level up, Machine	28
Cubchoo	Level up, Machine	30
Beartic	Level up, Machine	30
Glaceon	Level up, Machine	35
Froslass	Level up, Machine	40
Eiscue	Level up, Machine	42
Snorunt	Level up, Machine	45
Glalie	Level up, Machine	47
Spheal	Level up, Machine	48
Amaura	Level up, Machine	48
Articuno	Level up, Machine	50
Aurorus	Level up, Machine	54
Sealeo	Level up, Machine	58
Walrein	Level up, Machine	64
Squirtle	Machine
Wartortle	Machine
Blastoise	Machine
Psyduck	Machine
Golduck	Machine
Poliwag	Machine
Poliwhirl	Machine
Poliwrath	Machine
Tentacool	Machine
Tentacruel	Machine
Slowpoke	Machine
Slowbro	Machine
Shellder	Machine
Cloyster	Machine
Krabby	Machine
Kingler	Machine
Chansey	Machine
Kangaskhan	Machine
Horsea	Machine
Seadra	Machine
Goldeen	Machine
Seaking	Machine
Staryu	Machine
Starmie	Machine
Jynx	Machine
Gyarados	Machine
Lapras	Machine
Vaporeon	Machine
Omanyte	Machine
Omastar	Machine
Kabuto	Machine
Kabutops	Machine
Zapdos	Machine
Dratini	Machine
Dragonair	Machine
Dragonite	Machine
Mewtwo	Machine
Mew	Machine
Chinchou	Machine
Lanturn	Machine
Marill	Machine
Azumarill	Machine
Politoed	Machine
Wooper	Machine
Quagsire	Machine
Slowking	Machine
Qwilfish	Machine
Sneasel	Machine
Swinub	Machine
Piloswine	Machine
Corsola	Machine
Delibird	Machine
Mantine	Machine
Kingdra	Machine
Smoochum	Machine
Blissey	Machine
Suicune	Machine
Lugia	Machine
Mudkip	Machine
Marshtomp	Machine
Swampert	Machine
Lotad	Machine
Lombre	Machine
Ludicolo	Machine
Wingull	Machine
Pelipper	Machine
Azurill	Machine
Carvanha	Machine
Sharpedo	Machine
Wailmer	Machine
Wailord	Machine
Lunatone	Machine
Barboach	Machine
Whiscash	Machine
Corphish	Machine
Crawdaunt	Machine
Feebas	Machine
Milotic	Machine
Absol	Machine
Relicanth	Machine
Regice	Machine
Kyogre	Machine
Shellos	Machine
Gastrodon	Machine
Happiny	Machine
Mantyke	Machine
Snover	Machine
Abomasnow	Machine
Weavile	Machine
Mamoswine	Machine
Palkia	Machine
Tympole	Machine
Palpitoad	Machine
Seismitoad	Machine
Basculin	Machine
Frillish	Machine
Jellicent	Machine
Cryogonal	Machine
Kyurem	Machine
Keldeo	Machine
Skrelp	Machine
Dragalge	Machine
Carbink	Machine
Goodra	Machine
Bergmite	Machine
Avalugg	Machine
Xerneas	Machine
Diancie	Machine
Popplio	Machine
Brionne	Machine
Primarina	Machine
Wishiwashi	Machine
Mareanie	Machine
Toxapex	Machine
Wimpod	Machine
Golisopod	Machine
Pyukumuku	Machine
Type: Null	Machine
Silvally	Machine
Cursola	Machine
Mr. Rime	Machine
Arctozolt	Machine
Arctovish	Machine
Glastrier	Machine

Ultra Sun and Ultra Moon: 161 species

Species	Method	Level
Castform	Level up, Machine	20
Mamoswine	Level up, Machine	21
Spheal	Level up, Machine	36
Glaceon	Level up, Machine	37
Sealeo	Level up, Machine	38
Walrein	Level up, Machine	38
Amaura	Level up, Machine	38
Aurorus	Level up, Machine	38
Vanillite	Level up, Machine	40
Vanillish	Level up, Machine	42
Vanilluxe	Level up, Machine	42
Cubchoo	Level up, Machine	49
Snorunt	Level up, Machine	50
Seel	Level up, Machine	53
Beartic	Level up, Machine	53
Glalie	Level up, Machine	54
Froslass	Level up, Machine	54
Articuno	Level up, Machine	57
Dewgong	Level up, Machine	65
Squirtle	Machine
Wartortle	Machine
Blastoise	Machine
Psyduck	Machine
Golduck	Machine
Poliwag	Machine
Poliwhirl	Machine
Poliwrath	Machine
Tentacool	Machine
Tentacruel	Machine
Slowpoke	Machine
Slowbro	Machine
Shellder	Machine
Cloyster	Machine
Krabby	Machine
Kingler	Machine
Chansey	Machine
Kangaskhan	Machine
Horsea	Machine
Seadra	Machine
Goldeen	Machine
Seaking	Machine
Staryu	Machine
Starmie	Machine
Jynx	Machine
Gyarados	Machine
Lapras	Machine
Vaporeon	Machine
Omanyte	Machine
Omastar	Machine
Kabuto	Machine
Kabutops	Machine
Dratini	Machine
Dragonair	Machine
Dragonite	Machine
Mewtwo	Machine
Mew	Machine
Totodile	Machine
Croconaw	Machine
Feraligatr	Machine
Chinchou	Machine
Lanturn	Machine
Marill	Machine
Azumarill	Machine
Politoed	Machine
Wooper	Machine
Quagsire	Machine
Slowking	Machine
Qwilfish	Machine
Sneasel	Machine
Swinub	Machine
Piloswine	Machine
Corsola	Machine
Delibird	Machine
Mantine	Machine
Kingdra	Machine
Smoochum	Machine
Blissey	Machine
Suicune	Machine
Lugia	Machine
Mudkip	Machine
Marshtomp	Machine
Swampert	Machine
Lotad	Machine
Lombre	Machine
Ludicolo	Machine
Wingull	Machine
Pelipper	Machine
Azurill	Machine
Carvanha	Machine
Sharpedo	Machine
Wailmer	Machine
Wailord	Machine
Barboach	Machine
Whiscash	Machine
Corphish	Machine
Crawdaunt	Machine
Feebas	Machine
Milotic	Machine
Absol	Machine
Clamperl	Machine
Huntail	Machine
Gorebyss	Machine
Relicanth	Machine
Luvdisc	Machine
Regice	Machine
Kyogre	Machine
Piplup	Machine
Prinplup	Machine
Empoleon	Machine
Buizel	Machine
Floatzel	Machine
Shellos	Machine
Gastrodon	Machine
Happiny	Machine
Finneon	Machine
Lumineon	Machine
Mantyke	Machine
Snover	Machine
Abomasnow	Machine
Weavile	Machine
Palkia	Machine
Phione	Machine
Manaphy	Machine
Arceus	Machine
Oshawott	Machine
Dewott	Machine
Samurott	Machine
Panpour	Machine
Simipour	Machine
Tympole	Machine
Palpitoad	Machine
Seismitoad	Machine
Basculin	Machine
Ducklett	Machine
Swanna	Machine
Frillish	Machine
Jellicent	Machine
Alomomola	Machine
Cryogonal	Machine
Kyurem	Machine
Keldeo	Machine
Skrelp	Machine
Dragalge	Machine
Carbink	Machine
Goodra	Machine
Bergmite	Machine
Avalugg	Machine
Xerneas	Machine
Diancie	Machine
Popplio	Machine
Brionne	Machine
Primarina	Machine
Crabominable	Machine
Wishiwashi	Machine
Mareanie	Machine
Toxapex	Machine
Wimpod	Machine
Golisopod	Machine
Pyukumuku	Machine
Type: Null	Machine
Silvally	Machine