I truly dislike this game. I am usually a fan of Tower defense games. I can't claim to win all of them - for instance, I can't win Desktop Tower defense at the medium or harder levels.
But *this* game sucks. THe balance of the different components are all off. The creeps increase in hit points tremendously without similar increases in the bounty, which means that you don't get enough money to successfully upgrade your defenses.
The cost of the second tier of defense weapons is ridiculously high. So are their upgrade costs. And you don't always get that much additional firepower.
And how come the maximum levels of the sniper towers actually decrease their firing speed?
