Season 2 started off great, with "Lesson Zero" being especially outstanding, also finishing just as strongly. While the season mostly is a very watchable one with a fair share of great and interesting episodes, the quality of the episodes "Luna Eclipsed" onwards varied with also some disappointments, a couple of those disappointments being sadly mediocre. A word that no fan wants to call a 'My Little Pony: Friendship is Magic' episode, ever.
It is with sad regret to say that "The Mysterious Mare Do Well" for me was one of the mediocre episodes. Along with "Dragon Quest" and "Putting the Hoof Down" (though the latter at least had one awesome character), it is one of Season 2's worst episodes and in the bottom end when ranking the show's episodes overall too. The story just didn't engage, despite the episode starting off promisingly, and the characterisation is screwed up royally, which was one of the episode's biggest annoyances.
"The Mysterious Mare Do Well" by all means does have its moments. It is very colourfully and meticulously animated. The music is infectious and well fitting without being over-scored, syrupy or too chirpy.
Morever, the first couple of minutes are promising and there is a nice construction action sequence. The voice acting is very good across the board, then again that is not unexpected.
Unfortunately, the things that matter even more are far less successful. The story is very contrived with some choppy transitions, making one feel that the episode wasn't always feeling complete. The moral is poorly thought out, a good one on paper but sadly very heavy-handed and would have worked if the characters weren't so poorly written. Nobody is interesting. Nobody is likeable. Everybody is a jerk for reasons inexplicable and not explained, and everyone is stripped of what made them work so well as characters. Absolutely hated how Rainbow Dash was treated in the episode, and felt too that she came over as too naive. Then there are appearances that are random and too come and go.
Furthermore, nothing in the story is compelling or surprising and "The Mysterious Mare Do Well" does nothing to progress any characterisation (with the characters distorted beyond recognition). The pacing is both dull and choppy. The writing is neither clever or funny, and completely hollow emotionally. Found it near-disrespectful at worst too.
Altogether, a major disappointment and sorry if this comes over as too harsh to some. 4/10