You can't hold your mouse still with the button held and have moving blocks be destroyed. Instead of relying on MouseMoved events, use ButtonUp and ButtonDown so you can detect it when it doesn't move. For bonus points, interpolate a line between successive frames so a fast moving mouse doesn't jump over a dot.
Besides the fact that a game that requires two keypresses a level will occasionally miss a keypress, a game whose only interaction is a circle hitting a line cannot be excused for bad collision. Coding a circle colliding with the end of a line is _not hard_. It is an edge case that is easily handled. It is bugged when the circle looks to cling to the line and shoot off in the line's direction.
A whole new direction? Would that be towards suck? No next-wave button. One click accidental selling with cursor that looks like upgrade. Straight line map.
Impossible to be anything but full on everything unless you walk away from the computer. Anything that can hit you drops enough stuff to bring you back to full.
I wish I was able to choose an attack regardless of the correctness of the range, so when I know the other guy is going to Teleport in or Ninja-port away I can hit them with an attack instead of just being canceled.
Dude, the boss sentence needs spaces, and needs to come on screen all at once instead of only being able to start it when he's halfway over. You need to put up a warning when there is going to be an arrow-pressing sequence. The difficulty should ramp up sooner; I only get hit by the level boss fights, and I look at the keys when I type. There should be more things to spend money on; I only need to level one spell so I just sit on thousands of dollars. The shuriken guys can throw after they are dead. This game is such a 5/5, but these suggestions could make it a 6.
Things to make it even better: remove the ha-ha-I-have-a-scrabble-dictionary words from the normal enemies and make a type of enemy that only has wacked out words. Put more words in. Change how the archers work, because they are worse than useless; they cause me to get hit. Hiding the first letter of a word is not helping. It makes it harder to type. The archers could slow baddies down. Make some levels have sentences. The boss fights aren't clear when you have to hit two together vs in sequence.
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