Need option to redo levels. I'm 90% sure you forgot to include it at the final moment, since it says "best score" and "most cash," implying a replay option.
I can beat little forest easily. In fact, I grind it.
1. Add a warrior on the second tile. (second from the right). Upgrade him to energy, then consecrate, then general/tactician/unholy.
2. Just before the swarm of experienced rats, pave 4 tiles on the back 2 rows (the ones on the corners where they have to go around) and add 4 new warriors.
3. Just keep upgrading the main guy. Shouldn't have any problems.
Froze on level 5; the boss kept coming in and giving me 1 gold for killing him. Couldn't get to next level. Couldn't sell my units either.
Great start, but needs save, more variety in upgrades, and less super-powerful bow towers - I just spammed the level 1 ones and went crazy :D