A good try... But poorly executed.
Well, I have to admit, this game had me sitting here for the good part of an hour and a half, at least, and playing, playing, playing... However, despite how good it is, it is heavily flawed. Most of the towers have extremely variable usefulness, which makes it a tad annoying to play, when you need to put more of a certain type down, but it's range is not good enough to reach the enemy and gain EXP...
SM Missle: necessarily worthless.
This tower is the bane of my existance... It has ok range, and ok damage, for the price... However, it is simply worthless compared to anything else. I'd take a Slow tower over one of these any day... Though they do no damage. Even when they actually "hit" the enemy, more often then not, it deals NO damage! Why, oh why, would you put such a function into this game..? If thats some kind of "miss" feature, then it terribly needs to be removed. Increase the "damage" of these towers, and their accuracy, I beg of you.(I had to replay level 2 about 15 times to finally beat it, because of these dang things..
Ranger: Sniper-esque worthlessness.
These towers are almost a complete waste of time and space... They have insane range, yes, but they can't hit 70% of the time because their shots have to actually contact the enemy to have, A CHANCE, to hit. Just like the SM Missle tower, it is basically worthless. A remaking of this tower is in order, really..
Rapidfire: Multi Targetting Failure.
As with the SM Missle, and Ranger, this tower is also neigh worthless... It shoots at lots of enemies, with as much strength as the SM Missle, and EVEN LESS accuracy, if that is possible.(Hurt my brain so much trying to make them work...) Either make these faster firing with a guarantee to hit the enemy when they fire, or get rid of them. They are basically a waste of 500 bucks...
SM Tesla: Shockingly short range.
This tower had such potential... And got wasted. The attack is nice, it's fast, it's strong, it's effective... But TOO SHORT RANGE TO FUNCTION! I understand it is meant to be short range, but it is so short it cannot gain enough EXP to level, nearly ever! Increase the range, that is all it needs..
Other then that, I have no issues with the towers.. Slow and Drain are fine, but the rest are a waste of time and money. And speaking of money, I hnestly would have to say, please, PLEASE make a cash-upgrade system... EXP is fine and dandy, but late in the game, when you need more defense, and you want to stick some more towers in... You most likely can't put them close enough to the enemy to allow them to GAIN that EXP they need to level... Please, add some sort of cash-fueled upgrade system, so that towers can be upgraded manually, instead of being forced to wait for them to level on their own. I know it is part of the challenge, but it gets a tad ridiculous very, very quickly at times..
Also, concerning your "regenerator" zombies... GET. RID. OF. THEM. I'm aware they are meant to be powerful, difficult to destroy enemies, but 85% of the time, even if you have an entire squad of max level Drain towers blasting them, with Slow beams holding them down, they STILL manage to run on through, and take a bite out of your health. Please, don't weaken them, don't attempt to "balance" them, just remove them... They just bring headaches... They are not needed.
The last thing I would say needs adjusting is the monster running routes, more often then not, they tend to swarm a single side, and only trickle through the other, making it nearly impossible to determine which side you should reinforce before the round begins.. Maybe shrink the lanes a bit, so they have less room to run right out of tower attack range so very often, as they do currently. That would make the game much more enjoyableto play..
Other then those things, you did a very good job on this game, and I enjoyed it quite a bit. I wish you the best of luck on your future work, and hope you take a bit of my criticism to heart for this game.
Booyaka, Legoman.
-Cossack.