Heatran is in stark mountain
First you go to survival area and there is a house next to the poke center go there after you went through the Stark Mountain with the girl and took the stone.Next talk to the girl and old guy.If she says she is going back then leaves, then go to Stark Mountain again go to the last room and Heatran will be there. Watch out he is lv70. I suggest a master ball if you don't have one good luck.
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