I've collected all the gems but I can't get the last achievement. I think this is because the last gem doesn't register when you defeat the boss, yet oddly you still get the star
I really liked the game, it had beautiful graphics and an easy to learn interface. My only problem was the last level where you would be stuck in places you could not escape which made it seem more like luck than skill. Really enjoyed the pinball levels though
cannot beat nightmare - level 5, the swarm coming from all directions overwhelms all defences mainly because: 1) the screen is too small therefore your turrents can't hit anything until the enemy is right next to your buildings; 2) the AI of your units is stupid chasing enemies only within 1 portion of the screen at a time...
game is starting to lag in all the wrong places...middle of a battle...start of a battle...and sometimes won't even load the screen. Starting to become a pain because it eats up your energy regardless
Check the tutorial gem perhaps?