I'll be honest here -- I see where all the praise for this game comes from, but I bought it back when it first came out and was never able to play beyond the second or third colossus. The game was just too adept for its own good at making me feel like a selfish dirtbag for killing these creatures that were otherwise content to be left alone.
I don't know if I'll ever actually be able to finish it. I'd like to. But I don't think I have the heart.