Thanks for your feedback! Really glad you enjoyed it. We wanted to add horizontal movement, but there became several ways the player could exploit it, such as staying in the middle. Will maybe add it in the future with good balancing. We added the bubble system because sometimes the player could stay at the bottom and just press the keys for the colored enemies. Yes, I definitely agree that the game is difficult at the start. We are thinking about changing it by having fewer obstacles, colors, or a slower speed at the start.