Game is cool, art is going to be sublime, but I have genuinely no idea how anyone is supposed to beat the later levels. You get gold, but it feels balanced around a shop that doesn't exist yet.
Also, this kind of corruption is always best as a slow burn. I would draw it out, introduce recurring characters, build up a world, and give the protagonist some proper motivation. She could have a weapon to end the war, but she needs to attract the attention of the one in power to be able to use it?