You could use it for anything but I [and many others] stronly suggest that you save it for Cresselia or Mesprit. Even though you only have one, you can still use mean look to prevent the Pokemon from escaping. Hope this helps!!
In Diamond & Pearl, Cyrus
You should use it on one of the 'roaming' pokemon, like Cresselia in Diamond/Pearl/Platinum.
you get the master ball once you beat Cyrus in the galactic building
to get master balls..you must have a friend with action replay and trade you pokemons that will hold a master ball
in firered, mewtwo in platinum, diamond, and pearl, mesprit those are just suggestions. pick the one you like most
no not unless you trade a Pokemon who is holding a master ball that's what I did because I had diamond and pearl i just reset and start from beginning with pearl until I get master ball then repeat. So far I've got 79 hope this helps
well i dont know about diamond or pearl but there is a emerald cloning cheat if that helps
where do you get the second master ball in Pokemon pearl
there is no master ball in diamond and also great ball. but there is silver ball-silver ball is like a master ball.
giratina
All you have to do is go in the Galactic headquarters in diamond, pearl or platinum and fight Cyrus [The Boss that you face in the Galactic Building] and you have to beat him. When you beat him he will give you a Master ball and he will leave the Galactic building and head to Spear Pillar and will Summon Dialga. For more Information try to type on Youtube " How to get a Master Ball on Pokemon Diamond, pearl,or platinum " Bye!
No. You can only get one master ball. But you can get one from a friend or if you have a GBA game like emerald, leafgreen, ruby like those and have a master ball on your GBA save make a Pokemon hold it then in pearl or diamond go to Pal Park and choose the Pokemon with the master ball and 5 others from your box capture all of the Pokemon then you will have theMaster Ball