If you do not have enough free space in the ROM you want to hack, that will be impossible.
Free Space Finder
Platform(s): GBA Hack Tools
Type: Miscellaneous
Compatible with: Pokemon Ruby, Sapphire, Emerald, FireRed, LeafGreen
Supported OS: Windows
Type: Miscellaneous
Compatible with: Pokemon Ruby, Sapphire, Emerald, FireRed, LeafGreen
Supported OS: Windows
GBA Item Editor
With a simple-designed interface for even a beginner can use, this tool can change the number – the name – the description – the special values of that item.
Type: Item and Market Editing
Compatible with: Pokemon Ruby, Sapphire, Emerald, FireRed, LeafGreen
Supported OS: Windows
IconEditor
Have so many different Pokemon is good, but you have to notice their icons. Change them with IconEditor, a practical tool for editing Pokemon icons.
Type: Sprite and Icon Editing
Compatible with: Pokemon Ruby, Sapphire, Emerald, FireRed, LeafGreen
Supported OS: Windows
Item Image Editor
After finish editing the Pokemon icons, let’s come to the Item icons. Change them with the Item Image Editor, feel free to do so.
Type: Sprite and Icon Editing
Compatible with: Pokemon Ruby, Sapphire, Emerald, FireRed, LeafGreen
Supported OS: Windows
Map Editor of Happiness
Not only Pokemon FireRed can be hacked, adjusted with a tool but also Ruby – Sapphire – Emerald – LeafGreen… all the games of Gen III.
Type: Map Editing
Compatible with: Pokemon Ruby, Sapphire, Emerald, FireRed, LeafGreen
Supported OS: Windows
Advance Map
This tool is so famous for changing the Pokemon maps with so many different additions.
Type: Map Editing
Compatible with: Pokemon Ruby, Sapphire, Emerald, FireRed, LeafGreen
Supported OS: Windows
Advance Mart
You will have the rights to redefine all PokeMarts in GBA Pokemon games with Advance Mart.
Type: Item and Market Editing
Compatible with: Pokemon Ruby, Sapphire, Emerald, FireRed, LeafGreen
Supported OS: Windows
Advance Series
A great combination pack that all the Pokemon game makers must have.
Type: Miscellaneous
Compatible with: Pokemon Ruby, Sapphire, Emerald, FireRed, LeafGreen
Supported OS: Windows