S3 E13 - Fluttershy becomes a stand-up comedian, with a cutiemark of three balloons.
S4 E07 - Fluttershy becomes a batpony, with a cutiemark of three pink bats.

And this is how Fluttershy became a male surrealist artist with a moth-cutiemark.

^{You know, this reminds me of that ending to that one comic I read that one time  that didn't actually have an ending.}