It's a working real-time strategy game with understandable instructions, medals and characters from MLP:FiM and Castle Grayskull. That's about it.
I'm sorry, but your game reminds me of a quote from the movie Hudson Hawk: "I'll torture you so slowly, you'll think it's a career!"
Here are some of my observations:
- During the normal levels there are only minor increases in difficulty. The game would have been better off if there where only 3 levels before each boss with three times the diamonds. I'm serious: That change would have made a lot of difference.
- It's way too grindy - either the upgrade & buy costs are way too high or the diamonds are way to scarce.
- The mini-game is the same in every zone. Playing it for diamonds would only make sense if the player was a natural in it. Having to wait for 7 regular levels to play it again makes it harder to 'switch' to that game. A training-mode would have helped; or at least the option to store an unlimited amount of points.
- The bgm is too monotonous and the mute button is missing in most of the screens.
- Pinky Pie and Rainbow Dash have jerking leg animations which didn't look particular 'life-like'. Another example of how there was no attention paid to detail.
Let's talk strategy:
- In general the best strategy seems to be to upgrade the cheapest 'foot soldier' (Pipsqueak) the most and the rank 3 one (Snails) by one level (to fill the cool down period) and then just use theses two. All other troop-ponies seem to be there to leech diamonds away from the Mane 6 Ponies who are the only ones who really need the upgrades.
- Boss-strategy is to die 'just right', upgrade the castle for a miraculous full auto-repair so you can face the boss with full HP. Timing that right is boring and tedious.
As a summary, the whole game seems like a loveless clone of the "Epic War"* series to me - just without any special features and designed so that the player would have to spend the longest possible time playing it without having any feeling of accomplishment or reward. The only reason for players to keep playing this beyond the first encounter with the 2nd boss would be the Newgrounds medals. I can only speculate, but it seems to me you were bored with developing the game and weren't in the mood to playtest it properly - so you submitted the version you happened to have and called it a day. There's a lot of potential wasted on this one and I'm convinced with some additional hours of work, this could have been a fun game.
* And speaking of "epic"... Tagging something "epic" is just pathetic - especially when it's below mediocre...