Master Code for Leaf Green: 
00000554000A 
1003DAE60007 

999 Rare Candies: Leaf Green:- 
00000554000A 
101DC9B00007 
830050000000 
830050020000 

999 Master Balls: Leaf Green:- 
B9A1AACB D6F4419A

Unlimited Free Rare Candies

Sorry, this code is only for Pokemon Leaf Green:USA. Version.

77DB5497

D7EE8C96

Catch Trainer Pokemon (hold L=R b4 throwing Pokeball)

(Note: this is US only!! sorry)

Region: US/North America | Class: In-game Cheats
4D83B1BF
E0F5F507
8E883EFF
92E9660D
B6C5368A
08BE8FF4
90B4977C
C0151DC2

Catch Trainer Pokemon

Beware, as this code can "backfire". If you catch some Pokemon from the elite four, some of them may turn into bad eggs. And you can't get rid of Bad eggs because they never hatch and eggs can't be released. anyway back to the code.

Region: Unspecified | Class: In-game Cheats
4d83b1bf
e0f5f507
8e883eff
92e9660d
b6c5368a
08be8ff4

Walk Through Walls

Master
72BC6DFB
E9CA5465
56671F3A
6F4F4D6B

Walk Through Walls code follows

Region: Unspecified | Class: In-game Cheats
Walk Through Walls
509197D3
542975F4
78DA95DF
44018CB4 Master Code

8D671FD9 6F6BEFF2
78DA95DF 44018CB4

Rare Candy Code

06AB3172 BE88C550

Anti-DMA(needed)
8D671FD9 6F6BEFF2
78DA95DF 44018CB4

999x Masterballs
B9A1AACB D6F4419A

999x Full Restore
C7C0A4B5 7C27F37B

999x Max Revive
E10F51DE B156EBB0

999x Max Elixir
F896F42D 2877BE9A

999x Rare Candy
06AB3172 BE88C550

Pokeball acts as Masterball

Region: Unspecified | Class: In-game Cheats

87ACF659
707466DC
8BB602F7
8CEB681A

Master Ball And Rare Candies:

Master balls: 82003884 0001
Rare candies: 82025840 0044
These are code breaker codes not Gameshark.