Okay, simple little shooter. Only draw back I'd say is that when you click when over two or more planes you destroy them all. There also seems to be a tiny bug in the game somewhere as on occasion it says you've missed -1 planes.
The bat moves sooooooo slowly, should be like blat, blat, blat! Try reducing the area that it can kill spiders in and increasing the speed of the squashing. Would make it feel faster and add a little more skill required to play the game.
Oh, forgot to mention. As soon as you kill the last opponent on all the screens you only have a few moments before it goes on to the next level and if you haven't harvested all the hydrogen and sulphar and are almost out of fireballs you cripple yourself at the next stage. Maybe transfer existing stocks or let the player decide when they want to go on to the next level.
I've played around with and there are a couple of things I think could improve it. Rather than have the seperate screens that you transition between, having a scrolling screen that moves as your dragon flies would help improve it slightly.
In your help screens you've mentioned about all the different types of buildings and opponents that you come across but I didn't notice anything on the different types of fireballs and their relative strengths and flaws. Would be handy to know ahead of time or to look up so you can plan what you're going to do.
I've got to say the endurance does get annoying sometimes as you're having to spend enough time going back and forth anyway to deposit your sulphar and hydrogen anyway.
I'd have to agree with the other comments on this. If you have keyboard controls then please let me retry again by pressing a key without having to use the mouse.
To me it feels like the white box moves a little sluggish even though it moves faster than the oncoming coloured boxes. There are some moments where you can see an opening but unless you were already heading in that direction you simply can't make it as the white box just moves too slow. Pick up the speed of the white and it should help gameplay.