The second story of Gravity Falls Rule 63.
Silvia wants to bond with the kids by taking them out fishing, but when they hear rumors that a sea monster lives at the bottom of the local lake, they enlist Salls to take them on a boating expedition to prove it really does exist, so they can earn a reward.
Tropes present in this episode:
- Awkward Great-Aunt/Grand-Nephew and Grand-Niece Bonding Activity: Silvia takes Dana and Marcus fishing. Needless to say the twins are happy to go monster hunting with Salls instead.
- Brick Joke: Early in the episode, Dana explains she brought a portable version of her artists kit. Later on, when she takes out a camera, Mabel simply reminds her of said artists kit.
- Continuity Nod: Dana asks Marcus if they got any pictures of the gnomes they saw in "Tourist Trapped".
- Cool Boat: Averted with Silvia's rowboat, but played straight with Salls' boat, the S.S. Sassy Gal.
- Crazy-Prepared: Dana brings seventeen disposable cameras for the monster hunt. This is because she's smart enough to realize that cameras keep getting destroyed or lost during monster hunts.
- Gadgeteer Genius: Old Woman McGucket. She's the one who made the mechanical Gobblewonker and it turns out it's not the first time she's built something like this to get attention from family members and friends.
- Secret Handshake: Marcus and Salls have one.
- "Scooby-Doo" Hoax: The Gobblewonker turns out to be a mechanical monster that Old Woman McGucket built to get attention from her son.
- So Unfunny, It's Funny: Silvia, Salls, and Marcus all have their moments of this, which means that Dana is the odd one out, being The Comically Serious.
- Stock Ness Monster: The Gravity Falls Gobblewonker.