How can you get Gourgeist's different sizes?

Question

How can you get Pumpkaboo/Gourgeist different sizes?

Answer 1

It's actually really easy. You run around in the tall grass in Route 16 until you find the Pumpkaboo size that you want. The small and average sizes each have an equal average encounter rate, while the large is rare and super sized is really rare. It may be hard to tell them apart, but don't worry, you can get all the different sizes on the route! (what I did was run around and catch every Pumkaboo that I encountered until I had all of them :P)

Answer 2

It all really depends on your luck.
The only place to find them is on Route 16, in the super tall grass. Small and average size have an average encounter rate, while large size is rare, and super size is very rare.
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