you have get a soulsilver and get it there on the safaria zone
Lairon thrive in the Safari Zone. Breed to get Aron.
Yes.
You can't catch Rotom in heartgold.
Yes you can
you cant catch him in heartgold you can only get him in soulsilver
u cant
Granite Cave, off of Dewford.
white forest
You can't catch him in HeartGold. Only in SoulSilver. In HeartGold, you catch Kyogre in Embedded Tower. If you transfer either Kyogre or Groudon to the other game, you can catch Rayquayza
You can catch Ekans in Pokémon HeartGold in the Safari Zone in the Marshlands area.
the cave under cycling road
In the white forest.