It was a nice day in the underground. Why wouldn't it be? You had just saved monster kind. You sat in the grass picking at your shoe-lace when Undyne tapped you on the shoulder. "Frisk, are you playing volleyball or are you too busy with your shoes?" Undyne always knows how to make you laugh. Yet, you don't think anyone has ever beaten Sans at puns. You get up and hurry to the volleyball net. Papyrus throws up the ball and Undyne spikes on to our side. Sans simply conjured a small bone and propelled the ball away from us. The next time the ball is on your side, you smack it up then punch it sideways. It hit the net. Mettaton runs to get but in the process you notice something strange. There's a silhouette in a bushes branches. That can't be right? There's no one there for the shadow. You go take a look and what you see makes you jump. Sans trots over. "yo. you good?" He looks at you with concern. You nod. Suddenly, a big crack appears in the sky. No one would have noticed if it didn't start pouring lava.

A kid falls out of it. They look like you, but they have purple eyes and are wearing a jacket that looks nearly identical to Sans'. They give you a hand shake and say "Hi. I'm Fleet. Here to prevent the massive apocalypse of other universes.