Overheat is learned by 20 species by level and 100 by machine

Effect, in PokéAPI's words

“Lowers the user’s Special Attack by two stages after inflicting damage.”

Who learns it

100 species in all, 8 of 18 games shown

Scarlet and Violet: 85 species

Species	Method	Level
Chandelure	Level up, Machine	1
Scovillain	Level up, Machine	48
Litleo	Level up, Machine	50
Litwick	Level up, Machine	52
Pyroar	Level up, Machine	57
Cyndaquil	Level up, Machine	58
Lampent	Level up, Machine	58
Skeledirge	Level up, Machine	64
Moltres	Level up, Machine	65
Quilava	Level up, Machine	68
Typhlosion	Level up, Machine	74
Chi-Yu	Level up, Machine	75
Volcanion	Level up, Machine	84
Iron Moth	Level up, Machine	91
Miraidon	Level up, Machine	91
Ho-Oh	Level up, Machine	99
Charmander	Machine
Charmeleon	Machine
Charizard	Machine
Vulpix	Machine
Ninetales	Machine
Mankey	Machine
Primeape	Machine
Growlithe	Machine
Arcanine	Machine
Magmar	Machine
Flareon	Machine
Mew	Machine
Snubbull	Machine
Granbull	Machine
Slugma	Machine
Magcargo	Machine
Houndour	Machine
Houndoom	Machine
Magby	Machine
Entei	Machine
Torchic	Machine
Combusken	Machine
Blaziken	Machine
Numel	Machine
Camerupt	Machine
Torkoal	Machine
Groudon	Machine
Rayquaza	Machine
Chimchar	Machine
Monferno	Machine
Infernape	Machine
Magmortar	Machine
Dialga	Machine
Heatran	Machine
Arceus	Machine
Tepig	Machine
Pignite	Machine
Emboar	Machine
Zebstrika	Machine
Larvesta	Machine
Volcarona	Machine
Reshiram	Machine
Fennekin	Machine
Braixen	Machine
Delphox	Machine
Fletchling	Machine
Fletchinder	Machine
Talonflame	Machine
Litten	Machine
Torracat	Machine
Incineroar	Machine
Toucannon	Machine
Salandit	Machine
Salazzle	Machine
Scorbunny	Machine
Raboot	Machine
Cinderace	Machine
Carkol	Machine
Coalossal	Machine
Fuecoco	Machine
Crocalor	Machine
Charcadet	Machine
Armarouge	Machine
Ceruledge	Machine
Revavroom	Machine
Cyclizar	Machine
Annihilape	Machine
Koraidon	Machine
Gouging Fire	Machine

Legends Arceus: 2 species

Species	Method	Level
Cyndaquil	Level up	43
Quilava	Level up	43

Brilliant Diamond and Shining Pearl: 45 species

Species	Method	Level
Charmander	Machine
Charmeleon	Machine
Charizard	Machine
Vulpix	Machine
Ninetales	Machine
Mankey	Machine
Primeape	Machine
Growlithe	Machine
Arcanine	Machine
Ponyta	Machine
Rapidash	Machine
Magmar	Machine
Flareon	Machine
Moltres	Machine
Mew	Machine
Cyndaquil	Machine
Quilava	Machine
Typhlosion	Machine
Snubbull	Machine
Granbull	Machine
Slugma	Machine
Magcargo	Machine
Houndour	Machine
Houndoom	Machine
Magby	Machine
Entei	Machine
Ho-Oh	Machine
Torchic	Machine
Combusken	Machine
Blaziken	Machine
Loudred	Machine
Exploud	Machine
Manectric	Machine
Numel	Machine
Camerupt	Machine
Torkoal	Machine
Solrock	Machine
Groudon	Machine
Rayquaza	Machine
Chimchar	Machine
Monferno	Machine
Infernape	Machine
Magmortar	Machine
Dialga	Machine
Heatran	Machine

Sword and Shield: 56 species

Species	Method	Level
Chandelure	Level up, Machine	1
Turtonator	Level up, Machine	48
Litwick	Level up, Machine	52
Lampent	Level up, Machine	58
Victini	Level up, Machine	84
Volcanion	Level up, Machine	84
Charmander	Machine
Charmeleon	Machine
Charizard	Machine
Vulpix	Machine
Ninetales	Machine
Growlithe	Machine
Arcanine	Machine
Ponyta	Machine
Rapidash	Machine
Magmar	Machine
Flareon	Machine
Moltres	Machine
Mew	Machine
Magby	Machine
Entei	Machine
Ho-Oh	Machine
Torchic	Machine
Combusken	Machine
Blaziken	Machine
Loudred	Machine
Exploud	Machine
Manectric	Machine
Torkoal	Machine
Solrock	Machine
Groudon	Machine
Rayquaza	Machine
Magmortar	Machine
Dialga	Machine
Heatran	Machine
Darumaka	Machine
Darmanitan	Machine
Heatmor	Machine
Larvesta	Machine
Volcarona	Machine
Reshiram	Machine
Fletchling	Machine
Fletchinder	Machine
Talonflame	Machine
Litten	Machine
Torracat	Machine
Incineroar	Machine
Salandit	Machine
Salazzle	Machine
Blacephalon	Machine
Scorbunny	Machine
Raboot	Machine
Cinderace	Machine
Carkol	Machine
Coalossal	Machine
Centiskorch	Machine

Ultra Sun and Ultra Moon: 79 species

Species	Method	Level
Darumaka	Level up, Machine	42
Turtonator	Level up, Machine	49
Litleo	Level up, Machine	50
Darmanitan	Level up, Machine	54
Pyroar	Level up, Machine	57
Litwick	Level up, Machine	61
Volcanion	Level up, Machine	65
Lampent	Level up, Machine	69
Victini	Level up, Machine	97
Charmander	Machine
Charmeleon	Machine
Charizard	Machine
Vulpix	Machine
Ninetales	Machine
Mankey	Machine
Primeape	Machine
Growlithe	Machine
Arcanine	Machine
Ponyta	Machine
Rapidash	Machine
Magmar	Machine
Flareon	Machine
Moltres	Machine
Mew	Machine
Cyndaquil	Machine
Quilava	Machine
Typhlosion	Machine
Snubbull	Machine
Granbull	Machine
Slugma	Machine
Magcargo	Machine
Houndour	Machine
Houndoom	Machine
Magby	Machine
Entei	Machine
Ho-Oh	Machine
Torchic	Machine
Combusken	Machine
Blaziken	Machine
Loudred	Machine
Exploud	Machine
Manectric	Machine
Numel	Machine
Camerupt	Machine
Torkoal	Machine
Solrock	Machine
Groudon	Machine
Rayquaza	Machine
Chimchar	Machine
Monferno	Machine
Infernape	Machine
Magmortar	Machine
Dialga	Machine
Heatran	Machine
Arceus	Machine
Tepig	Machine
Pignite	Machine
Emboar	Machine
Pansear	Machine
Simisear	Machine
Zebstrika	Machine
Chandelure	Machine
Heatmor	Machine
Larvesta	Machine
Volcarona	Machine
Reshiram	Machine
Fennekin	Machine
Braixen	Machine
Delphox	Machine
Fletchling	Machine
Fletchinder	Machine
Talonflame	Machine
Litten	Machine
Torracat	Machine
Incineroar	Machine
Toucannon	Machine
Salandit	Machine
Salazzle	Machine
Blacephalon	Machine

Sun and Moon: 78 species

Species	Method	Level
Darumaka	Level up, Machine	42
Turtonator	Level up, Machine	49
Litleo	Level up, Machine	50
Darmanitan	Level up, Machine	54
Pyroar	Level up, Machine	57
Litwick	Level up, Machine	61
Volcanion	Level up, Machine	65
Lampent	Level up, Machine	69
Victini	Level up, Machine	97
Charmander	Machine
Charmeleon	Machine
Charizard	Machine
Vulpix	Machine
Ninetales	Machine
Mankey	Machine
Primeape	Machine
Growlithe	Machine
Arcanine	Machine
Ponyta	Machine
Rapidash	Machine
Magmar	Machine
Flareon	Machine
Moltres	Machine
Mew	Machine
Cyndaquil	Machine
Quilava	Machine
Typhlosion	Machine
Snubbull	Machine
Granbull	Machine
Slugma	Machine
Magcargo	Machine
Houndour	Machine
Houndoom	Machine
Magby	Machine
Entei	Machine
Ho-Oh	Machine
Torchic	Machine
Combusken	Machine
Blaziken	Machine
Loudred	Machine
Exploud	Machine
Manectric	Machine
Numel	Machine
Camerupt	Machine
Torkoal	Machine
Solrock	Machine
Groudon	Machine
Rayquaza	Machine
Chimchar	Machine
Monferno	Machine
Infernape	Machine
Magmortar	Machine
Dialga	Machine
Heatran	Machine
Arceus	Machine
Tepig	Machine
Pignite	Machine
Emboar	Machine
Pansear	Machine
Simisear	Machine
Zebstrika	Machine
Chandelure	Machine
Heatmor	Machine
Larvesta	Machine
Volcarona	Machine
Reshiram	Machine
Fennekin	Machine
Braixen	Machine
Delphox	Machine
Fletchling	Machine
Fletchinder	Machine
Talonflame	Machine
Litten	Machine
Torracat	Machine
Incineroar	Machine
Toucannon	Machine
Salandit	Machine
Salazzle	Machine

Omega Ruby and Alpha Sapphire: 70 species

Species	Method	Level
Darumaka	Level up, Machine	42
Litleo	Level up, Machine	50
Darmanitan	Level up, Machine	54
Pyroar	Level up, Machine	57
Litwick	Level up, Machine	61
Volcanion	Level up, Machine	65
Lampent	Level up, Machine	69
Victini	Level up, Machine	97
Charmander	Machine
Charmeleon	Machine
Charizard	Machine
Vulpix	Machine
Ninetales	Machine
Mankey	Machine
Primeape	Machine
Growlithe	Machine
Arcanine	Machine
Ponyta	Machine
Rapidash	Machine
Magmar	Machine
Flareon	Machine
Moltres	Machine
Mew	Machine
Cyndaquil	Machine
Quilava	Machine
Typhlosion	Machine
Snubbull	Machine
Granbull	Machine
Slugma	Machine
Magcargo	Machine
Houndour	Machine
Houndoom	Machine
Magby	Machine
Entei	Machine
Ho-Oh	Machine
Torchic	Machine
Combusken	Machine
Blaziken	Machine
Loudred	Machine
Exploud	Machine
Manectric	Machine
Numel	Machine
Camerupt	Machine
Torkoal	Machine
Solrock	Machine
Groudon	Machine
Rayquaza	Machine
Chimchar	Machine
Monferno	Machine
Infernape	Machine
Magmortar	Machine
Dialga	Machine
Heatran	Machine
Arceus	Machine
Tepig	Machine
Pignite	Machine
Emboar	Machine
Pansear	Machine
Simisear	Machine
Zebstrika	Machine
Chandelure	Machine
Larvesta	Machine
Volcarona	Machine
Reshiram	Machine
Fennekin	Machine
Braixen	Machine
Delphox	Machine
Fletchling	Machine
Fletchinder	Machine
Talonflame	Machine

X and Y: 70 species

Species	Method	Level
Darumaka	Level up, Machine	42
Litleo	Level up, Machine	50
Darmanitan	Level up, Machine	54
Pyroar	Level up, Machine	57
Litwick	Level up, Machine	61
Volcanion	Level up, Machine	65
Lampent	Level up, Machine	69
Victini	Level up, Machine	97
Charmander	Machine
Charmeleon	Machine
Charizard	Machine
Vulpix	Machine
Ninetales	Machine
Mankey	Machine
Primeape	Machine
Growlithe	Machine
Arcanine	Machine
Ponyta	Machine
Rapidash	Machine
Magmar	Machine
Flareon	Machine
Moltres	Machine
Mew	Machine
Cyndaquil	Machine
Quilava	Machine
Typhlosion	Machine
Snubbull	Machine
Granbull	Machine
Slugma	Machine
Magcargo	Machine
Houndour	Machine
Houndoom	Machine
Magby	Machine
Entei	Machine
Ho-Oh	Machine
Torchic	Machine
Combusken	Machine
Blaziken	Machine
Loudred	Machine
Exploud	Machine
Manectric	Machine
Numel	Machine
Camerupt	Machine
Torkoal	Machine
Solrock	Machine
Groudon	Machine
Rayquaza	Machine
Chimchar	Machine
Monferno	Machine
Infernape	Machine
Magmortar	Machine
Dialga	Machine
Heatran	Machine
Arceus	Machine
Tepig	Machine
Pignite	Machine
Emboar	Machine
Pansear	Machine
Simisear	Machine
Zebstrika	Machine
Chandelure	Machine
Larvesta	Machine
Volcarona	Machine
Reshiram	Machine
Fennekin	Machine
Braixen	Machine
Delphox	Machine
Fletchling	Machine
Fletchinder	Machine
Talonflame	Machine

Changed over time

One change since Generation III

1. Through Gen VPower 140130 from X and Y, Generation VI