I have always loved My Little Pony: Friendship is Magic, and the parodies that surround it. I have also always been a dedicated fan of the fanfictions and fanlore that surrounds it as well, especially the stuff that seems strange. While I am not usually a fan of gore and horror when it comes to MLP:FiM, this is largely an exception because it is well...hilarious.
Animation / Graphics - The animation was truly well done, even I cannot contest that. I would have to say my favorite part of the flash had to be the faces that Pinkie made when torturing Rainbow Dash, and the faces Rainbow made as a result of that. I also paid special attention to the lack of wings, and deflated/sewn stomach of Rainbow Dash after each act was committed, and I have to say that I love your dedication to continuity.
Story - The story was always a lovely one, mainly due to the fact that you would never suspect Pinkie to do something so horrid, but I have always appreciated that small dash of insanity that she appears to have in her. I personally think the fans that make these stories do a wonderful job, largely due to the fact that they keep true to how Pinkie would act in any given situation.
Audio - The music was a wonderful selection for this animation, and I can honestly appreciate how well it fit the humorousness of this flash. It sounds so intimidating and depressing that it actually compliments the bright, cheery, happy aspect of the torture of Rainbow Dash.
Overall - One of the better My Little Pony animations I've seen, while not the funniest, this is a wonderful flash, and I hope to see more work from you in this field. Keep up the good work!