Grey Goo is the main character. He can eat anything that smaller then itself. His apparance is that of a slimy grey ball with 2 adorable eyes. In Tasty Planet, his eyes are above his head. In Tasty Planet: Back for Seconds his eyes are in front of his head. In Tasty Planet his story begins whith the scientist that created him.
In Majora's Mask, the Moon is the ominous object that threatens to destroy Clock Town in 72 hours during Link's adventure in Termina. By the power of Majora's Mask, it had been pulled from its orbit and destined to crash into Clock Town, which would obliterate the town along with most of Termina. The Moon also appears to lesser effect in Ocarina of Time and The Wind Waker, mirroring its real life counterpart with identical phases, size, and transit direction across the night sky.