The Legendary Pokémon that are in Pokémon Black and Pokémon White regardless of it naturally available within the games or not are Victini, Cobalion, Terrakion, Virizion, Tornadus, Thundurus, Landorus, Reshiram, Zekrom, Kyurem, Keldeo, Meloetta and Genesect.
Regigigas
all the ledgendary Pokemon are the best they are equal
Defeat all the gym leaders and then legendaries will appear on the maps.
If it is a ledgendary Pokemon (meaning there is only one of it in the game), them no
no ledgendary can breed (apart from manaphy to get phione)
Contrairy to the previous answer, Zekrom is wrong. the ledgendary Pokemon in Pokemon black version is Reshiram and Tornadus. hope i helped! - Raven and billsofat
Yes, yes there is: Keldo. A ledgendary water/fighting pokemon that you can only get in Black/White or Black/White 2
No,it is not
no
no delibird is not a ledgendary Pokemon
Regigigas
No, it's not.
Nooooooooooooooooooooooooooooooooooooooooooooooooooooooooooooooooooooooo
yes
it depends there is cobalion is a fight and steel type there is virizion a grass and fight type there is terrakion a rock and fight type those are three ledgendary Pokemon there is also kyurem a dragon and ice type hus also a ledgendary Pokemon in the last one is tornadus you can find also sundrus only an Pokemon white in tornadus only in Pokemon black if you have tornadus in sundrus in one game like inpokemon black in Pokemon white if you have those two in whan game that i said you can wake up anthor ledgendary Pokemon
Heatran is a ledgendary in Pokemon platinum.
Giratina