You have to have three different games for that to happen.
Trade for them.
You get them in different cities at the beginning of the game
My game is glitched at the beginning, it tells me the season then freezes all i see is Summer on a black background
You get one at the beginning of the game, and the rest you have to trade.
yes the Pokemon black and white games are on all three NDS, NDS lite, and NDSi ( XL )
If you havent beaten the Pokemon league then level them up a bit then defeat the Pokemon league
you need to have gameshark and enter 0100bad7 but don't get all three it will mess up the game.
The only way to get Tornadus in black is to trade from Pokemon white. Please note that all three Legends are very hard to catch and will flee at the beginning of the encounter. I would consider catching a Wynaut or a Wobafet to prevent it from running away. acally you get tornadus in black by following it around unava you were talking about thunderdus
You can get all three but you need emboar, serperior and samurott.breed it with a ditto at the daycare and you can get snivy,tepig and oshawott eggs
all the pokemon
Get another black or white like a cousins or friends. Then you start three new games and each one with each starter and trade the first two to the other black or white and on the third on you trade them back to have all three
no you can not