I really really really love the idea of something living and crashing into the earth, possibly burying itself deep within the earth. (pardon me, I just finished playing through Chrono Trigger for the millionth time, and I loved when Lavos crashed into the earth and left an enormous crater and etc. I could go on and on about this game.) The maps also look gorgeous, though, and I particularly like the water effect on the second to last one. Not sure which I would call my favorite though, since they're all good.