Game is visually very pretty. I love the shooting up animation and the dragoons sounding like Kirby noises. Art style is peak. Neon pastel vibes.
I have few stuff to nitpick... the only way I can see the "Chain Reaction" theme fitting is in the plot.
If you can spam click, there's literally no downside to shooting everywhere constantly.
Shooting dragoons is questionable, I hope there's hospital nearby or Doki is using allot of rubber bullets.
I never saw the big dragoon on the 2nd level...? Maybe spam clicking killed him too fast...
In the main menu, I couldn't select the instruction option, it just goes straight to gameplay. Had to resort to mouse options. I think somehow the mouse position was offset such that hover over instructions actually places mouse collision over the gameplay.
Otherwise, good work!