Great concept, and I really like the two phases: first building and then letting the world get blown away. I found it a bit easy overall - and in fact, couldn't work out how to lose a level! For future development, perhaps consider a physics engine for the spiderweb - eg, individual web lines that are linked (think World of Goo). Box2d could help with this (I'm currently quite biased though, as I've just been learning that for one of my projects - and have been blown away by how excellent it is). T