From Bulbanews, your community Pokémon newspaper.
To be distributed throughout October
A Super-Size Pumpkaboo will be distributed via Nintendo Network from Oct. 1 to 31. It will be holding a Rocky Helmet and has the moves Trick-or-Treat and Scary Face. It will be available for both American region and PAL region games.
It is being distributed to promote the Trick-or-Treat Friendly (which had been tentatively titled the Halloween Party in English until today). In the friendly, all players must have a Super-Size Gourgeist on their team, so this Pumpkaboo will make it easier to obtain. Pumpkaboo come in four sizes, and Super-Size is the least common.