I have Pokemon Black, and as far as i know you cannot catch event legendarys without an event (eg. Genocect, Zorua).
You cannot catch some Pokemon on the game, but Pokemon White can, and White can't catch some Pokemon that you can catch on Pokemon White.
Lol!
I believe it is just what Pokemon appear in what location, how often they appear, and what legendary you meet. And White Forest vs Black city (go to serebii.net to find out what those are.)
Because you don't have the pokemon in the pokedex
Black spots will appear in water when there is a Pokemon there, the Pokemon will be less common than the others on the route
it makes wild Pokemon less likely to appear
It does appear anywhere in black OR white only in platinum, soulsilver, and heartgold.
Genosect event.
He does not appear in Pokemon Black or White. He only appears in Gold, Silver, Crystal, HeartGold and Soulsilver if you want to battle him.
You can never trade Pokemon from Black to Platinum, because Generation V Pokemon do not appear in Platinum or any other game before Black and White. However, you an transfer Pokemon from Platinum to Black after you beat the game.
Braviary (as well as it's pre-evolution, rufflet) does not appear in the wild in Pokemon Black version. You will have to trade with somebody who has Pokemon White version. Likewise, Vullaby and Mandibuzz can only be caught on Pokemon Black.
Solosis Duosion Reuniclus Rufflet Briaviary Petilil Lilligant Thundurus Zekrom Those Pokemon are exclusive to Pokemon White
You can only transfer it as it does not appear in the game normally.
The game was programmed to appear 3D, but it won't appear as true 3D on the 3DS