Imagine: you are alone on your Amtrak train (I'll be honest I don't understand much of who you are or what you do, I like to imagine you drive all of the trains personally, and also grant admission to all passengers as well), the train is not scheduled to depart any time soon, you are naked, you are not expecting anyone to board the train.

You hear a knock at the train door, which are you more shocked to find when opening the train door?

A walrus,

Or

A fairy.