You should use a quick ball. If that doesn't work lower it's health and chuck ultra balls
The best ball is the mast ball, but if you want to save it use the quik ball. If you don't have them a minshao would work well. the n start throwing dusk balls
i'm sorry to say that you can't catch black kyuram in black and white. i've tried every way i can think of. but you can get it in black 2 and white 2.
Zekrom, and the best way to catch it is to keep your master ball and catch it that way, cause that's how I did it.
the best way to GET legendaries is by action replay. and the best way to CATCH legendaries is lowering there hp and catching them. or choosing the right pokeball:masterball,ultaball,repeatball,greatball,and pokeball.
cheats
with a net and they are not real
To catch use minno or a bunch of worms. But the best way to catch them is in the evening on a flyrod.
the best way is a master ball or a net ball when it is at 1HP
go to route 2 and use the pokeradar the best way to catch it is to use a master ball.
The Fire Path is the best way to go
you can get some rat trapes for £20
Throw a masterball at it.