Pinkie Pie, as she lies on the ground in the diamond dogs' mines, while Spike shouts his second big "NOOO!". Taken from the episode "A Dog and Pony Show".
The vector is self-made in Inkscape, using the episode picture as reference. Download for full resolution.
And if you want to see her SMILE:
This time: An oddly calm picture of Pinkie. I think "sprazzled" describes her in her own words rather well, it's Pinkie!
I don't know if I'm really happy with the outlines, I used a different technique this time...
And now with extra sharp edges!