Too much dialogue imo for a boss rush- Its more like an interactive visual novel. I didnt see any Spin, but it was likely bc I stopped playing soon after the first battle bc of the amounts of text
Some sound effects between dialogue (ie the sound of a door opening, chains clanking, or character voice bytes) would help a lot, also maybe different expressions depending on the dialogue. Some custom graphics (like a cutscene but just a single image) would also help break up the monotony of dialogue
Loved the art!