You buy it at Mauville game corner for 4,000 coins
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You can find the TM Flamethrower in the Game Corner in Goldenrod city for 10,000 prize coins.
TM35 (Flamethrower) is located in the Abundant Shrine.
at the game corner
You can trade a Pokemon that is holding the TM from diamond to soulsilver or pearl or platinum or you can migrate a Pokemon holding the TM from ruby, sapphire or emerald or firered or leafgreen.
at the mauville game corner
Tm. 35
Flamethrower is TM 35 and you can buy it in the celadon game corner
There's no tm for it. Pokemon can only learn it.
You can get TM 25 (Flamethrower) at the Mauville Game Corner for 4000 coins.
TM35
TM35.