Ah, ok, i tested your map.
and found a lot of bugs and problems.
1-its impossible to research pulverize.
2-the same problem for the spirit walker, no upgrades for him.
3- enemy units are the same all the time. (pigs,golens and lizards -.-)
4- this could be a TD. i build something like 24 towers, and only let thrall distract the enemies. why do we need units? also the damage of the towers are greater than any of my units, and 1400 range?

"
5- terrain have many problems, my units couldn't move because of the short space, there is a LOT of unused ground in the map.There is a cave on the top of the map, you could send some centaurs from there. in fact, you should create a new map.
6-the itens for the hero are completely useless. and cannot be used by my units, making the backpack upgrade useless too.
also the description is poor, i vote for
rejection, im sure you can do better then this.