The shadow in Mount Snow is a shadow in Kart Kingdom. It had never been used until Kart Kingdom Racing was added and just sat there. It was originally next to K's Tent. It is now under one of the three people standing next to the Kart Kingdom Racing entrance. The picture you see right now was taken before racing was added.

It is unknown if it ever was going to have a use, or if it was a glitch that was never removed, or if it was just an easter egg of some sort.

Some people think it could be ice, others say that it could be a shadow. It is unknown if it is ice or a shadow, but its called Shadow in Mount Snow because most people think its a shadow, and there's no official name for it.