Emerald exclusively has the Battle Frontier and also contains battle animations. Ruby and Emerald have a greater variety of sound effects, differing bikes, Pokémon contests, and Secret Bases. Both Ruby and Fire Red have ongoing 649 patches and Fire Red has a hacked game engine available. Emerald can be considered the most advanced of the three versions however it also contains the least documentation of the three and its architecture differs from both Ruby and Fire Red making working with it slightly harder. It also improves, in areas, on the implementation of certain features in Ruby. Fire Red has a larger amount of documentation and consequently hacking it is easier. The most notable distinction between the three is the resources available. The three main ROM bases for generation III are Fire Red, Ruby, and Emerald in order of popularity - LG and Sapphire are rarely used for hacks. Generation III (R/S/E + FR/LG) is by far the most popular generation to hack due to the large tool pool and the ease of entry.

That said there's great resources over at the Skeetendo forums and we generally know the most about this generation. Generation I (R/B/Y) and II (G/S/C) hacking is 'old skool' at this point in time, and a little more complex than generation III due to the lack of tools. So you've decided you want to make a hack? You need to decide which generation and specifically which game version you want to use.

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