If you have already used up your one masterball, you need a cheat to get more. You can only get one master ball legally on the game. The following link contains the cheat code for this, and tells you how to do it. Good luck!
http://www.gamefaqs.com/portable/gbadvance/file/918915/32496
Trade masterballs from other games to firered.
Silph co.
You have to get a codebreaker and put in the master code. Then you have to find the code for infinite masterballs on the computer.
the way to catch all legendary Pokemon in the Pokemon universe is lokk at the number they are in the pokedex then thro away that many masterballs you have to have the cheat where you get 999 masterballs to do it
You get the masterball when you go and defeat Team rocket
No but you can have a friend trade you a Pokemon holding the masterball they got.
u dont :)sry mwarriors1019
there is tons of treasures there go by the health center back side you will find another masterball all together you can find up to 25 masterballs there
just make a Pokemon hold a master ball and trade it.....if you have the patience to do that over and over that is.
There is no way to get unlimited masterballs atleast without a gameshark or hacking the game hope i helped
i don't think that there is a way... like i got some on mine but its still kinda a cheat. i got two gameboys, firered, leafgreen, a connector cable, and an action replay. i used the action reply to get 100 masterballs onto my leafgreen account. i gave a masterball to 6 Pokemon on my leafgreen account. i traded them to my firered account on firered i took the masterballs from the Pokemon on leafgreen i gave the Pokemon more masterballs then i traded again i just repeated this over and over until i got 100 masterballs on firered the reason i didnt want to just put the action replay directly with firered was because that account was really powerful and the action replay sometimes messes it up. my leafgreen however, was really weak so it was worth the "risk".
You have to get an action replay or a game shark. Other than that its impossible.you can't there's only 1 in the game