Hello,
This game is quite interesting and pretty fun to play. Here are a few suggestions to improve this game and make it more action-packed -
1. Currently there are no visual effects for enemy dying or bullet shooting. So adding particle effects or any visual element could give good user feedback.
2. We could implement the screen shake on bullets colliding with enemies.
3. Addition of different SFX on shooting and colliding.
4. Increasing the difficulty of the game gradually.
5. Introducing more variants of enemies with different abilities.
6. Introducing powerups and other such things.
7. Evolving the player as the game grows gradually making him powerful.
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