There are another ways to get money rather than locking some feature. Just like Mardek 3, the dev make the music from the game is downloadable for some money. He makes money without making his fans get disappointed.
Get exp from every battle you won (without making a new highscore ) will make this game much more relaxing. I don't care if the exp needed to level increase significantly, I'm stressed to make new highscore in every map to level up!
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