I'm to lazy to keep doing this so here's a danh sách of all my theories and some evidence.
-Dipper's real name is Issac. In Fight Fighters, Dipper enters the initials D.I.P, which could stand for "Dipper" Issac Pines.
-Gideon is a vampire. In Weirdmegenton 1, Gideon says, "She was always meant to be mine". I guess this means that he's a vampire cause ma cà rồng are immortal. There is also other stuff that supports this and bạn can look it up on YouTube, but I can't help bạn there.
-Bill is still in Dipper's mind. In Northwest Manor Mystery, Dipper reacts to Mcguckets warning with the line, "Let's have some fun for once". He doesn't care and he walks of with his fits on his hips a thing only Bill did when he was possessing Dipper. Also in Stan's Not What He Seems, there is that one scene where Dipper's eyes look like how they did in bít tất, sock Opera when Bill was possessing Dipper.
Um...I can't think of anything else. So, I'll just get back to đọc and nghề viết văn fanfics.