Id most likely do anything. Being a human has worn its welcome on me a bit. It would be wonderful to be reborn as a Pegasus and hang with the mane 6 and all the other ponies. If there was a legit decision to have to do something big to go to the MLP universe id probably kill myself, kill a stranger, burn a town, etc.. But those things would not be tasks to be let into equestria, celestia would not allow that. The hardest test that can be given to a human who wants to live in equestria would to become the human with the most friends. That test is hard because there are celebrities that have thousands, maybe even millions of friends. For a normal person that would be extremely tough to do but would prove your worthiness to live in equestria