The vampire dog is a banner pet! You have a random chance at getting a banner pet in place of a token when you click on a trick or treat banner ^^
For future questions regarding the Halloween event, I would recommend asking here, on the 2021 Halloween Event - Help, Questions & Answers thread c:
|x|x|x┌─────────────┐ |x|x|x|x|they / he | trades |x|x|x||||||||||||||cs help |x|x|x└─────────────┘ |x|x|||"the hunt is everything, |xand the pack is always ready"
The actual ratio of receiving a banner pet : receiving a token is not released. So far I have found 76 candies + 1 banner pet and have seen others with roughly similar ratios or no banner pets at all.
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hi hi hi
SEEK WHAT SETS- ─ YOUR SOUL ON FIRE ┌─────────┐
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Chinese | GMT+8 full time foodie fire type pkmn! :>