He's faking it, Sans. (Undertale x Gravity Falls Crossover)

Weirdmageddon didn't just open the portal between the dream realm and the real world, it also opened up the portals to all worlds. One of them being Undertale. As a result, when monsters escape the surface, they find themselves by Gravity Fall on the summer after Weirdmageddon.

But there's a problem. When Grunkle Stan's memories were brought back, so was Bill. He's back this summer, and wants revenge.

Oh, and now he wants Sans. Things get weird. Again.

(original cover go brr)