Love the idea. I could definitely feel the Undertale influence filling me with the determination required to beat this challenging game! I especially love the ending. The dialogue is so funny and feels like a proper reward. Rushing to the end while a thousand pigs are chasing you felt really good.
There where some issues I had though. You can't walk all the way to the bottom of the screen which limits your ability to dodge and it irritated me a little bit. I'm guessing you did this so the character can't walk through the boss later when he appears.
I found the the controls for the rhythm part of the game very awkward. I don't know if it is a standard layout but as someone who doesn't play rhythm games it felt unnatural. Because the arrow keys aren't in the same relative positions as they appear on the screen the player has to translate every arrow to their actual position. The random rhythm generator also sometimes gives a rhythm where up and down have the be pressed at the same time, which feels very awkward as you have just one finger for both buttons. I would suggest you to rather use the 'j', 'k', 'l', ';' row of buttons to make it feel natural.
The music was great. I played again just to hear the boss music once more. If you made that music yourself I say very well done.
All the little touches of dialogue where so funny. Keep those up in your next game :) !!!
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