This page is my prediction for what will happen in each episode of season 2B.
Episode 1. This episode will pick up right where Not What He Seems left off. It will focus heavily on Grunkle Stan and the author's backstory, but I don't think the entire episode will be flashbacks. I think it will also at least address the issues raised in the previous episode, such as the government agents still being all over Grunkle Stan, the entire world hiccuping, and Dipper's feelings towards his family. This episode will end on a small cliffhanger, probably about Dipper's feelings. Type: mythology.
Episode 2. This episode will pick up the morning after episode 1 leaves off, and will focus on the cliffhanger from that episode. An all new monster, as well as an all new major mystery, will be uncovered. A long-standing problem will also be dealt with in this episode. Possibly the author will sacrifice himself for his family. This would do four things: first, it would get the cops off Grunkle Stan's back. Second, it would allow him to get up close and personal with Gideon, and therefore he might be able to convert him to the good side. (Or Gideon might convert the author to the dark side!) Third, it would keep the author from revealing too many secrets. And fourth, it would effectively take him out of the picture until the writers want him again. And the episode will all end in time to let us down easy back into the normal world of Gravity Falls. Type: combination mythology and monster of the week.
Episode 3. This episode will "set the tone" for the half-season. Something will happen in this episode that will be a recurring theme throughout season 2B. For example, in The Golf War, the Pines made nice with Pacifica. This would happen a lot as many of the Pines' season 1 enemies became their friends. Something similar will happen with this episode. The events of the last few days will be mentioned, but not really used in the plot. Type: monster of the week.
Episodes 4-8. These episodes will give you an update on all your favorite characters, plot lines, and mysteries. There will be more monsters, more mayhem, more mystery, and more of everything that makes Gravity Falls great. Every major character will make an appearance. We will also likely get updates on unseen characters, like Gideon (who still will not have broken out of prison!) and Bill, but not a lot will change. Type: one monster of the week, one mythology, one combination, one anthology, and one toss-up that could be any of the first three.
Episode 9. This episode will be more normal. Another long-standing issue will be resolved. There will be a lot of review in this episode. Whatever happened in episode 3, that was a recurring theme throughout the season, it will happen again in episode 9. It will be one of the stranger episodes and will kind of show off the entire half-season in a nutshell. Exactly one plot development will happen in this episode. Type: monster of the week.
Episode 10. This episode will start out normal. An old foe will reappear, but they will not be the antagonist. I see Gideon possibly returning in this episode, either as a changed boy or with a new minion: the author. This will be a monster of the week storyline for 20+ minutes, then it will blindside us with a cliffhanger. The cliffhanger will be hinted at at least twice in prior episodes. Type: combination.
Episode 11. The cliffhanger from the previous episode will take place late at night. This episode will pick up on it the next morning. There will be a ton of secrets to explore in this one. If Gideon returns in the previous episode, I wouldn't be surprised to see a move from Bill in this one. Maybe the prophecy of Bill's Wheel will be fulfilled. I do not see the series ending here, though. I see the season ending on a major cliffhanger we barely understand, and that cliffhanger being picked up either in the third season or Gravity Falls: the movie. Either way, you do not want to miss this episode. Type: mythology.
