I think you may have misunderstood one of the contest rules. Regarding #4
"Game Length: Judges will only be required to evaluate a game for 1 HOUR if it passes the screening stage. Any game over 1 hour will be judged only on its first hour of gameplay."
It just means that if you developed a game that lasted longer than 1 hour, they will only judge the first hour of it. If the game plays in less than an hour that doesn't matter. For example they would be free to if they didn't defeat the boss in their first attempt try again unless it would take them past an hour of play, or if they think they've experienced enough of the game to judge it before then they won't need to play again.
Yep it uses dragonbones animation for the boss and player characters, happy to hear you liked them :) (credit to the original artwork though is http://www.akashics.moe/ for the monsters and http://woestijn.deviantart.com/ for the characters.) Glad I had time to animate the characters and that you liked that.
Happy to hear you like the twist on that mechanic ^^. Yeah, the challenge of the battle is observing the boss's actions, preparing and trying to eliminate monsters as efficiently as possible with new abilities learnt, and best removing those sponges so you can defeat the boss. Regrettably I didn't have time to add more variability into the enemies actions, I just focused on the characters and the overarching boss's stages and polishing that, thinking if interest grew with the base system there I could certainly add a new boss later with more complex minions and strategies to face.
If you'd like to try another project any time, an earlier game I designed does have more varied enemies and different overlapping systems, with a growing challenge and 'currency' you can use to not make your characters stronger but customize the layers of challenge with highscores you can gain http://i.imgur.com/hQ10GmP.png . You can find it here.
Thank you for trying out the game, I'm happy to hear you'd like to see it evolve further as a lot of the work I did was just getting everything functional, so I'd have a lot of fun just adding new content and Boss/enemy challenges to it now :).
You're probably right about the contest rules thing, it's all good :)
Overall though you definitely got a solid premise! It's the sort of game that if developed further (more content, maybe a bit more polish where necessary) it could easily be up for sale on Steam.