Recently, Stanley called you up to visit him in Gravity Falls. You didn't know why, but you'd be happy to help an old friend. You knocked on the door of the cabin he was in, and it suddenly burst opens.

"WHO IS IT?! HAVE YOU COME TO STEAL MY EYES?!" He held a crossbow pointed at you before facing it down.

"Oh.. It's you... Good... Come in and hurry, I need your help."

He leads you down to the basement where the upside down, triangle portal with symbols around it is at.