The TD Grind
I noticed right off the bat that the game was terribly slow. Luckily there is an option to speed it up, which I found myself simply clicking on each time before starting. This made it possible to even get the "expert" status, as your points tick down all the same in between waves.
The first few maps were certainly easy. I kept at it in the hopes that the difficulty would increase, which it abruptly did. I found myself having to play older maps to "grind" my way up to being able to handle the newer ones. I'm not sure I liked that style, I would have preferred to rely more on strategy and less on passive bonuses.
I didn't play long enough to find much use for the multi tower, freeze tower, or poison tower. I tried to incorporate them, but they felt terribly weak.
All in all I had a fun time for a while with this, but I felt that it was too demanding on the grind and that the "special" towers just didn't cut it. I found myself just using the first two towers for the first 11 levels before eventually giving up. Good work on the game, overall, but I feel like it still has a way to go to really be fun and addicting.