My one criticism: some levels didn't require you to really think for yourself. You just clicked until the section of the picture moved/changed itself to the correct position/picture.
Tip: If there is only one enemy left during a wave, get close to killing it, but do not kill it until it gets close to your tower. This will give your tower more time to heal and your spells more time to cool down.
The shadows, 3D effect with the tress/pillars, the particle effects, and just generally beautiful pixel art pretty much makes the entire game, because other than that it's a pretty normal (actually slightly more boring than normal) RPG with a good story.
I'd like an endless or sandbox mode because, with all the new towers and such, I'd like to be able to play around (and there's the need to strategize later on and in harder modes).
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