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I was hoping that Nastyjungle or Yilx's designs would win, because they seemed to best represent the typing AND stat spread Imo. But Mos-Quitoxe's art is great and I still think it does a good job representing the typing and stat spread. I love the little lava lamp on its back!
Of the four, I feel like Cyzir's, and Mos's get the feel of a pokemon across the best. Doug's is pretty close, but really, I could see Cyzir's in the show with little trouble.