My opinion of this game is that it's a game with a solid foundation and some clever ideas that are hampered by a number of obnoxious, crippling problems. This game does have some good features: the graphics are pretty darn good for pixel graphics and actually look nice rather than like the work of someone who can't be bothered to put effort into art. You don't see too much of that on Newgrounds. The idea of an idle game with health, damage, healing, and RPG mechanics is interesting. This is where the good ideas end. Here are my grievances with the game.
To begin with, the clicking and powers are useless. By level 33 even a frenzy of x2 damage clicks barely did anything to my enemies, and that's with my clicking damage at a higher level than any of my heroes' levels. The cost of increasing clicking damage and the cost of increasing the warrior's damage is the same, but the warrior's damage increases much faster, and is therefore the obviously superior investment in products with exponentially rising costs. As other people have already said, the powers have too little an effect for too long a cooldown.
Also, the game continuously lags and needs time to load, even on my new, rather powerful computer. This is an inexcusable flaw for an idle game. Why should I have to wait a few seconds for the game to load every time I buy one level of an upgrade or kill a few enemies? The computer I use can run much more complicated, graphically sophisticated games without lagging or needing to load, so this game puzzles me.
The game's difficulty curve is too steep. The number of levels I need to gain, and consequentially time and money I have to put in, to defeat a boss increases drastically with every boss I fight. Even after upgrading all my heroes' levels by about 50% I still almost die, losing more than half my HP with each boss attack.
In short, lag, the short-falling of click damage, and monsters that quickly become nearly unbeatable are problems that make what would've been a decent game simply an exercise in frustration.