The unsolved mysteries of Gravity falls

Trouble

While we were waiting for Stacy's dad to come we sit down in the snow discussing the problem that kept Stancy and her dad in Artarctica.
-Sorry guys, but I can't remember anything. After I send Peter that message someone or something enter our house and atacked dad. The next thing I remember is that I was a wolf and someone shot me with a seringe and then I wake up and you were with me.
- Maybe you got amnesia.
-Or maybe someone shot you with a Memory Gun.
-No, amnesia or memory guns doesn't leave you with rendom pieces of you memories. Only one thing in this world could make this,I said. A dream demon, like my father.
- Then your father have a sibling.
-But his dimension was fired up by him. There were no survivors. Only him.
-Yes, but maybe someone escaped without him noticing.
-Yeah, maybe.
-Wait a second! You are alone here, right? No more humans?
-Nup, no more humans, only strange creatures.
-Then, the only one who could be possesed, the only one who can shot you.......
-THAT'S RIGHT KIDS!said a strident voice behind us. I HAVE A NEW BODY NOW!
Blood freeze in my veins. Horified, we turn around. There, in front of us, stayed Stanford Pines with a creepy smile on his face and a loaded gun full of seringes. His eyes were blue as ice and his pupils thin as a snake fang. He was possesed.