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Version Differences
Pokémon Blaze Black and Pokémon Volt White are available in a variety of versions. There is the "Normal" version, which is the main version of the hack, having every regular Pokémon wild and all changes to other things applied. There is the "Legendary" version, which is very much like the Normal version but is different in that legendaries are also catchable around Unova, albeit rarely. Lastly, there is the "Clean" version (of both the Normal and Legendary versions) that brings the hack back to the bare basics of wild, trainer and evolution differences.
You can also choose a hacked version of Black or White, implied by the name. There are no exclusive wild Pokémon this time around, but Black and White maintain their other usual differences such as aesethetics and catchable legendaries. Black City has been edited whereas White Forest has not, however. There are also slight differences between Drayden and Iris' teams, as well as one small change in N's team between versions.