Most of a TDG

This was the first of my half-built game projects. It was only made to see how hard it would be.
I thought a Tower Defense Game would be easy to program the basics and the interesting more complicated stuff would be added later.
The game would get more difficult: when enough monsters had come the game would either make more monsters per second, or make the monsters a little faster.

Having a hotbar-complete with instructions and selection buttons-shows how compete the game was when I stopped working on it. pressing D would activate a debug menu, when pressed the game would draw the range of the towers, and draw a line from every tower to its target; very useful when everything would break.

with my friends this game requires the least amount of explanation, and is the closest to a full game.
They think the game is too unbalanced. The yellow turrets are far better than the red turrets, so when using red turrets the game is impossible to win, but the yellow turrets make the game too easy to be difficult.
If I had more time I would have added more types of towers, and monsters to make the game more difficult.