Simple weaken it to red HP then use a move to make it sleep constantly throw pokeballs until you get it.
A Repeat Ball.
master ball
depends on which game. IN Pokemon hg/ss the dusk ball is the best. In r/s/e timer balls and ultra balls. Watch out for fissure and double edge
great ball
you can use master ball in caught the groudon
go to the eight town and use master ball
A poke ball costs 200 poke's (in game money) A great ball costs 600 poke's An ultra ball costs 1200 poke's But you can't by a master ball but you get one just by playing.
You buy it at any poke mart
YHEA!! I caught groundon when i threw 1 heavy ball at it with full health
When you beat the Champion go to Steven's house. There will be a poke ball. There will be a Beldum in the poke ball.
U can use a poke ball,mega ball,ultra ball but try it from the first when it appear with a quick ball it can catch it faster.
dusk ball heal ball master ball poke ball a lot of balls will work all balls will work! that sounds odd