People, I can assure you, this game is most definitely older than Realm of the Mad God. Its official release date was June 20, 2011, and this was even uploaded to Kongregate in 2010 (considering, you can't confirm that's the original release as well). Great Dungeon in the Sky uses Oryx's sprites, and so does RotMG. Perhaps attempting research might befall the truth onto you, and make SOME of you stop criticizing the game for its similiar style.
Nice job on making the music, bro! You should make more games. Not only the music, but also the animating and the levels are pretty good too. I give this a perfect 100 stars.
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Glad you enjoyed it!