Really well-executed game, the theme fits and the atmosphere/story is really funny :D
It's also a 'blast' to play and it feels great to see enemies fly off into the sky after a good hit!
Small things:
- Hitboxes should probably be more generous, having the blast radius of the shot also hit/affect the enemies
- Cannon should maybe have a trajectory line for the start point of the shot, that then fades the further away you are trying to shoot
- Enemy train should give feedback then hit (Visually or via. audio)
- Your trains smoke gets in the way visually while trying to shoot
- Maybe have a top bar for total distance traveled in comparison to the end goal
Great game, keep it up!