Nice work! I played your game and really appreciate the effort you put into creating it. The vertical scrolling shmup concept with dragons and gold has potential for sure! I like how plentiful the gold is so it's easy to get a high score.
I noticed some areas that could use improvement though. The music, while catchy, felt a bit repetitive after a while. Maybe adding some variety or dynamic elements could enhance the overall experience.
Additionally, consistency in the size of fireballs and adding death animations or explosions could make gameplay more engaging. Sometimes my projectiles were super tiny and other times looked really big.
I also found that the health power-up (The green + sign) didn't have much impact? I wasn't sure what that did since the dragon still faces one-hit death from enemies. Maybe it could be like a shield that absorbs one hit?
Overall, I see potential in your game and hope these suggestions can help you refine it further! Keep up the great work!