The ability to traverse two regions of the pokemon world hasn't resurfaced since Gold and Silver (Heart Gold and Soul Silver don't count because they're remakes). In addition 2nd gen maintained the basic pokemon feel, aside from a few rejects (Smeargle, Snubull, Chinchou, and a couple others).
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You know, I used to have this fantasy that the next Pokemon game would have some way of getting online, and would contain 4 world maps and 350 pokemon, as well as at least 100 hours of subquests. Then the GBA games came out, and I started hunting for at least a way to get back to the old regions of the world. When I realized I'd checked every single part of the game, I cried.
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