Mega Pony is a My Little Pony-inspired Mega Man game (Or perhaps a Mega Man-inspired My Little Pony game, depending on your view) created by a fellow named Khao Mortadios.
The fairly simple plot of the game is that the Mane Six have been corrupted by Discord after they defeated him, forcing Celestia to call upon MegaPony to save them (as well as defeating Discord).
Following that, the player is prompted to start the game, to which they're then greeted with the mane six's evil portraits and a choice of which stage to start with. Once all six stages and the Mane Six have been "beaten", the Discord Fortress segment begins, which culminates in Discord's defeat.
Not a whole lot to say about the story. Of course, the game was not created for the story specifically.
The music compliments the cross-over aspect of the game by being remixes of both Megaman songs AND MLP songs. All themes are well-adapted to the 8-bit formula and are fairly catchy, thought that may be largely because of the original tunes themselves.
Graphic-wise, most of the sprites are unique and made from the ground up for this experience only. There are some cases of enemies such as the Metool being an obviously re-used sprite though.
The gameplay is what the crux of this experience is all about though. Well, that and the crossover aspect, I suppose.
The stages introduce many gimmicks and "teaches" players how to deal with them. These gimmicks later resurface in the final stages in much more difficult fashion in order to test the player's nerves and talent. There are also many enemies with simple attack patterns strewn about stages in an intentional fashion (for the most part). Players should beware of butterflies flying out of pits, or Wonderbolts seeking them out and kicking lightning into them.
Many creatures and characters are directly based off the show, or are a "ponified" version of a Mega Man character. Speaking of which, MegaPony himself is essentially Mega Man ponified. There's even a power-up that allows you to switch the sprite to the humanoid version (with a few inconsistencies).
But there are some disjoints when it comes to balance, namely in the first 6 stages: Rarity's is extremely unforgiving in its first half, being an on-rail autoscrolling section (with isn't what the rest of the game is like) culminating in a fight against a mini-boss, yet its second half is quite possibly the easiest segment of the entire game. Most new players would probably struggle greatly on that stage, as several gameplay functions that are supposed to allow things to be easier, such as infinity lives, have no practical function there.
On the other hand, you have Fluttershy's stage, which while isn't particularly easy or difficult, gives a tremendous amount of rewards in its first section, especially with the right power-up, making it the best farm zone for goodies and gems. Gems can be used to buy common and unique items in the shop (which can be accessed on the stage selection menu). This means her stage is by far the one players are likely to go to for acquiring these things.
Inexperienced players may be tempted to try either Applejack or Twilight's stages first, as they have very forgiving designs.
The bosses themselves also have a fairly erratic difficulty pattern. The Mane Six are fairly equal, but some clearly have more complicated designs than others: namely, when Rainbow Dash's health begins getting low, she'll start using a far more difficult move to avoid, turning her from a simple opponent to a deadly one (with the right setup though, this can be circumvented). Fluttershy and Rarity also get stronger patterns as they get weaker. Yet when Applejack, Twilight and Pinkie Pie begin losing too much health, they get no such thing.
Speaking of which, while many of the patterns for the mane six boss fights respect the character's origins, Applejack gets a strange machine to pilot in her fight. There is no explanation as to why she uses the thing or where it came from. It perplexes me why the creator of this game couldn't figure out a boss pattern for her that wouldn't require incorporating something so alien to the character, given that all the other ponies have very recognizable moves, such as Fluttershy's stare, Twilight's teleport, Rainbow Dash's dash, Rarity's gem-finding spell or Pinkie Pie's party cannon.
You'd think Applejack, if she truly needed an external device to figure out a boss pattern for her, would have gotten Bloomberg (a tree), or one of her family members.
Instead she gets a shallow fighter robot that sucks up apples, fires them and punches.
Are you kidding me?
Still, this is only a minor nitpick in the final product. Once the game is beaten, the Mane Six become playable, and they all get movesets that respect the character's origins, including Applejack's (which just raises further questions as to why her boss fight needed that robot).
While there is more to this game than this, it may be best for those of you reading to find out about the contents of Discord's fortress yourselves, as there are some neat surprises for fans of the show My Little Pony: Friendship is Magic.
Mega Pony can be downloaded over here.
Or you can watch my commentary playthrough over here (spoils everything!)
Overall, Mega Pony is an enjoyable cross-over game for experienced platformer players that they may want to look into, especially if they enjoy the show it was inspired by. Inexperienced players may find the game to be a bit too frustrating in some segments, however.