Moon

The moon was a puppet of Majora's Mask during Link's adventure in Termina. It had been pulled from its orbit, threatening to crash into Clock Town to ruin the Carnival of Time. To even show the fate to the townspeople, it had an evil face creeping across it. It would destroy Clock Town in three days if Link didn't do anything. One of it's interesting points is that it always faced south. Another thing is inside of it was a beatuful meadow hazy like a dream. The only thing to break it is a single tree. You'd figure it out once you played the Oath to Order after freeing the four giants. It opened its mouth, its eyes started to glow, and it says:

"I- I shall consume- consume- consume everything."

The moon is one of the many mysteries of Termina that will probably never be solved.