the one region pokemon games never visited. back in 2005, the pokemon tcg rolled out its delta species series and, with it, a brand new setting called holon. this isolated land was built around a giant research tower. the story followed scientists who ran experiments with electromagnetic waves. the experiments went wrong, scrambling the dna of the local pokémon and producing mutated versions of them. these mutants were known as delta species. rather than keeping their usual types, many well known pokemon were given totally different elements. dragonite turned lightning, gyarados became fire, mewtwo became metal, and dozens more got bold new types and looks. for a few months, pokemon tcg had a full sci-fi tale set in holon. then, almost as fast as it appeared, the whole era faded away and was never revisited.