Simple and compelling. Really liked hatching new monsters and levelling them up. Linking the economy to how you clean up after these little monsters fun and silly.
I wish there were more visual and audio queues during combat to make it more clear that your monsters are engaging in a fight. I would drag a monster onto an enemy, but it would walk away because I mis-clicked, resulting in my crystal's destruction.
Can't wait to see how these creatures evolve! great game!