Just Wondering. Because If you really do need all the now unavailable event Pokemon too I'm In trouble!
You do not need event Pokemon to complete the Pokedex. You only need the Pokemon that are obtainable in-game.
In HGSS, you only need to see the Pokémon in order for it to count toward completion (of the Regional Dex). Event Pokemon are not required for either Dex completion award.
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