The normal 1 from Professor Juniper in Mistralton.
You can get 2 Master Balls in both versions.
XD
Only one everyone knows that unless you hack your game
By regular game play, only one Master Ball is obtainable. However, the TV station in Jublife City offers a lottery system where you are allowed to draw a lotto ticket once per day. The lotto ticket contains a number, and if the number matches any of the ID of your Pokemon, you will win a prize. The prize depends on how many digits matched. If all the digits match, you will win a Master Ball. Another way to obtain Master Balls is by trading or migrating Pokemon hold Master Balls into your game. *Cloning, otherwise known as cheating, a Pokemon holding a Master Ball is an alternative method. To learn how, GOOGLE: Cloning Pokemon In Pokemon Diamond and Pearl. Clone at your own risk. Dangers may be fatal to your game.
Infinitely. You just need to match all 5 numbers on the lotto ticket to one of your Pokemon's ID.
You can get 2 Master Balls in both versions.
18 but under certain occasions check on the pokemon website when
you can get 1 master ball
1
i masterball
one
1
You can clone a Pokemon with the master ball or trade it to a friend and keep starting over until you're satisfied with the number of master balls.
Attach your master ball to ONE POKEMON, next CLONE that Pokemon for how many master balls you want. Next detach them, and release all the clones (if you want)
Duplicate Pokemon with a masterball attached to them.
Only one.
I think you can get only one.