Board Thread:Questions and Answers/@comment-5131007-20130908192632/@comment-10751008-20130908201223

On the Breeding Structure, there are holes in the two pipes emitting pufts of red-orange steam. If it is unmuted, It makes a sound associated with steam, for lack of a better description. I'm not sure if the actual sound produced varies with each island. I also can't confirm if it acts as another monster, in the respect that it contributes to unconditionally muting some of your other monsters if you have too many singing at the same time, as you've said in your "Over singing" post. For that reason, I just leave them muted since they don't really make a big contribution to the song.