One of the very few 'idle' games that's good. My only suggestion is a re balance of the defense/tower life system. Currently, it doesn't appear balanced. For no matter how much I put into it, the enemies attack points increases much faster than I can upgrade the tower life, meaning they will always 1-hit kill me.
Other than that, great game!
Rewards are set WAY too low. Bosses are way over powered every 5 levels, making you have to play level 4, 9, 14, 19, etc. over and over and over...and over...and over...just to get gold/XP to progress. Otherwise the concept is nice.
 "The Perfect Tower"){kind=icon}
 "Stormbound"){kind=icon}
 "Enchanted Heroes"){kind=icon}