Rayquaza is a Pokemon from the third Generation. Pokemon Gold is a second generation game.
Pal Park
To get reyquaza in pokemon rumble blast you have to do tower areas over and over again. If you do this the "!" Launcher will be sparkeling. This will lead you to a battle with reyquaza unless you have beaten the EX royales in axel town, then it could be reyquaza or arceus I think.
they are kyogre, reyquaza, and latias.
sky pillar on the sky pillar on rt 114
Migrate from Emerald, sapphire, ruby, or trade with heartgold and soulsilver
first u must have TM fly then get back to sky tower after that you must reach the top until you meet reyquaza again
Pokemon Heart gold is different from Pokemon Gold cuz heart gold has better graphics new Pokemon and new events
Pokemon gold johto
Witchcraft.
if you mean Pokemon gold then the answer is no and if you mean Pokemon haert gold then you can get him only with action replay
There is no pokeathelon in the original Pokemon gold
i don't know about a gold Pokemon but magikarp when it is shiny is gold