Sans was in the woods, when he heard something. A strange person walked out and introduced himself. "Who are you?" Sans asked. The stranger looked a lot like him. "Why I'm Sans. Error Sans. I came from another dimension. Actually, that's why I'm here. I want to show you some dimensions." He said. He was really glitched out, and so was his voice. Suddenly, glowing blue strings wrapped around Sans' soul, and dragged him into a portal. He called out Frisk's and his brother's name, and Papyrus came running just to see Sans disappear into the strange portal. Underfell Sans was walking around Snowdin. He heard a voice. "Over here! Go left! In that clearing!" Sans, curious about it, followed it. He came into a clearing in the woods. Suddenly blue strings grabbed his soul, and wrapped around his arms to prevent him fighting back, and he saw a white portal open, and someone inside, pulling on the strings. Then he passed out.