Definitely 5/5. The only flaws are magic is hard to use (should be hotkeys) and ether potions are overpriced. And there should be a boss/rare creature per 5 or 9 levels.
This could be an awesome game but it's so low effort even for Armor Games. It needs click-to-move, inventory while in town for starters. And for some reason a skinny little snake is a bigger threat than an armored, sword-wielding human. Character customization is limited to your name, no stat selection, one gender. Gear and quest selection are purely linear and all grind. 1/5 for not putting 25% done in the title.
I have a suggestion to make ninjas less annoying but still unseen sometimes. First off the ninja's skill is called smokebomb but really they just walk by defenses. So, instead of this I think it should be an actual smokebomb-like effect that they have a 10-33% percent chance of using when hit, where a 4x4 (5x5 for bosses) tile area is covered and anything in it, not just ninjas, is unseen. 5/5 for the best TD on Kong.
Awesome game, really fun. Lags a bit but not too bad. I'd 5/5 it but you can purchase (and don't deny that it's purchasing) ingame currency so it's 1/5.