Quote Originally Posted by Cleobel View Post
Here is the easier way to obtain the 3 segment form : a Hardy Dunsparce with the ability Serene Grace obtained in a gen 3 or 4 game has a 50% chance of evolving into a 3 segment Dudunsparce (after being transferred to Scarlet and Violet via Pokemon Home).
Any other Dunsparce from gen 3 and 4 games will always evolve into a 2 segment Dudunsparce, unless it was obtained in Pokemon Colosseum.
Indeed, any Hardy Dunsparce from Pokemon Colosseum (regardless of ability) has a 25% chance of evolving into a 3 segment Dudunsparce, and any Pokemon Colosseum Dunsparce with a different nature will always evolve into a 2 segment Dudunsparce.

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Thank you very much, that's fascinating!

Although I think if I want to shiny hunt one, catching Dunsparce in SV will be my best option. And it'll give me lots of shiny Dunsparce and 2-segment Dudunsparce to give away.