Spike, as he looks up to the umbrella hat that Pinkie Pie tossed up in the air. Taken from the episode "Feeling Pinkie Keen".
The vector is self-made in Inkscape, using the episode picture as reference. I tried to achieve a professional high-quality vector.
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It's strange: almost in every vector of Spike he has an extreme look. There need to be more "casual Spike" vectors!