A note: I reached level 14, but upon restarting the game I was reset back to level 2 with an E in level 1 (I don't even know what an "E" rating means) and lost everything I'd gained up to that point. Is this a bug in the game? If so, can it be fixed? I love this game but I'm not willing to play through every lower level and grind for upgrades every time I want to play my favorite bosses.
 "Bit Heroes"){kind=icon}
 "Civilizations Wars"){kind=icon}
 "Bullet Heaven"){kind=icon}