nothing
When you beat the elite four.
I would train all your Pokemon until they are all about level 75 or a little less.Hope I helped:D.
Yes they do I can tell you from experience.
you need to beat the elite four on both games
Yes
They are still in the Pokemon league
nothing
When you beat the elite four.
You can use a strong Pokemon to hit all the Elite four's Pokemon and champion Lance's Pokemon (in HeartGold). It depends on your Pokemon level but you can use ice types to beat Lance's Pokemons so it's easy to beat Lance.
You go beat the elite four and capture lugia/ho-oh.
I would train all your Pokemon until they are all about level 75 or a little less.Hope I helped:D.
viridian forest in the kanto region after you beat the elite 4 for the first time you can go there
no but when you beat red you will beat the game fully (without catching every pokemon) and the elite four will become twice as good as before
no u dont
i beat them in heart gold by trading lv 100 dialga from diamond that worked well for me so give it a try
no beat the elite four first