Using dusk balls at night tend to work the best. But if you get it to sleep, an ultra ball can work too.
Use a dusk ball instead during the nighttime.
Master ball
get him down to low healt then use an ultra ball
Before you find Dialga in Diamond or Palkia in Pearl or giratina in platinum, Cyrus will give you a master ball. I'm assuming this is so you can catch Palkia, Dialga, or Giratina.
you cant, you will need a master ball. I wasted mine catching Dialga yes u can use a heal ball i did it b4 im proved by pkmn master
Defeat team galactic then use it to catch giratina :)
If you havn't used you marster ball yet use it
All you have to do is use the master ball
use a master ball
Master Ball
it is easiest to catch him with a heavy ball made by Kurt in azalea town with a apricot
With a master ball.