Use your mouse pointer to aim at the red enemies. No arrow keys are needed. Your cannon automatically shoots. If the red enemy reaches the blue part of the cannon, you will lose 2 health per second as long as an enemy is touching it. The goal is to survive as long as possible & gat the highest score you can. When you die, click on the green flag. The high score won't be reset.
I drew inspiration from the enemies from my project Zombie Shooter Remix, which is a remix of Zombie Shooter by @ProgramingPotato I am planning to update it eventually. Plz give feedback in the comments. Keep it nice or someone will report it if not me.