You don't need a certain type, you can use even a normal Poké Ball. Different Balls have different effects. Since legandaries have very low catch rates, I recommend using Ultra Balls (Save your Master Ball! It would really stink to need it and not have it!). You should also bring along Dusk Balls if it's night, Timer Balls if it takes you a while to get to red health and basically as many as you can.
Remember to save your game before catching it!
A master ball
U have to use a poke ball or any types of poke balls like master balls or ultra balls. But firstvu need to find it. Then go up to him then click then battle then catch
Darkrai can be caught in any kind of Poke Ball, but Ultra Ball has 4x the catch rate by itself, which is pretty high.
Just throw a some Ultra balls, Heal balls, Luxury balls, Premier balls, standard Poke balls, and Dusk balls if you're in a cave or capturing the Pokemon at night. Keep throwing the same kind of Poke balls until the Pokemon can get out very easily, then use a different kind. This might take a while. It's easier if you capture the legendary Pokemon at night, so more Poke balls are effective. (Dusk balls)
you go get poke balls and catch Pokemon. that simple mmk
Dusk balls
Master Balls, obviouslt
Any.
You need a lot of ultra balls and a lot of dusk balls
to catch a caterpie, you must first have poke balls and some weak pokemon. you weaken the caterpie down to red health and the throw your poke ball. if this does not work, keep on throwing your poke balls until it eventually works. hope this helps.
use poke balls on it
Catch them with Poke Balls. Or buy the game if that's your question.