I like this game, but there's no way it should be the top-rated game on Kongregate (which it currently is). The Gemcraft and Protector games are much deeper and much bigger.
Found a bug when I was trying to upgrade my grav gun after the latest patch. The upgrade cost "undefined" dollars, and when I upgraded I ended up with "NaN" as my money. Turns out this meant I effectively had unlimited money. Now I have 540 max hit points, my workers repair 212 Hp per wave, my trainer trains my troops for 427% more xp, and my loot is 941% more valuable. =)
Okay, the toad boss isn't too hard...ample use of the super arrow while throwing arch angels and paladins at him to stall him will bring him down. But afterwards it gets buggy; after the text intro, instead of taking me to the battle I just get a battle UI (buttons to summon and upgrade things), but instead of the battlefield, I still see the map. Anyone else have this problem?
Level 19 is not unbeatable. In fact, I'm on level 40 right now. The trick is to forgo the fireball and go with the sword upgrade and regeneration for Malak. I find that, in combination with purple, grey, and yellow gems, this setup will get you the rest of the way through the game, though some levels will require a few replays to figure out the right placement strategy.
 "Cursed Treasure: Don't Touch My Gems!"){kind=icon}
 "Copy Cat"){kind=icon}
 "Elona Shooter"){kind=icon}
 "Epic War 2"){kind=icon}
 "Orbs"){kind=icon}