Marco and Star go on a camping trip, and King River unexpectedly joins them.
Tropes:
- The Cameo: Soos from Gravity Falls can be seen among a group of tourists.
- Description Cut: When told that King River can find a ride to Old Youthful, Marco says "that would be nice". Cut to them riding a rampaging grizzly bear and being chased by rangers.
- Disproportionate Retribution: After getting bitten by a mosquito, Star's first instinct to to cast a spell that sounds like it's meant to cause the entire species to go extinct.
- Fish out of Water: King River is used to camping in the rather more dangerous wilderness of Mewni, and is once again rather lost at sea on Earth.
- Going to See the Elephant: Marco wants to show Star the Old Youthful geyser, especially when a park ranger tells him this might be Old Youthful's last eruption (though he turns out to be lying to mess with tourists).
- Gross-Up Close-Up: We get a close-up of Star's arm covered in mosquito bites when she shows off the "love bites" she got from nature.
- Missing the Good Stuff: Marco, Star and King River arrive at Old Youthful just as it's finished erupting, possibly for the last time. Subverted when it goes off again, just as King River falls into it.
- Nature Is Not Nice: Downplayed. Marco has to remind Star and King River that nature on Earth is not as savage as it is on Mewni. "Here, nature is nice." That being said, Star gets bitten by mosquitoes, and King River is scalded and thrown high into the air by a geyser, but both of them take these injuries in stride.
- Nice Job Breaking It, Hero: King River causes nothing but trouble for Marco and Star, up until he races them the ten miles from the ranger station to Old Youthful, on foot.
- Old Faithful: Old Youthful is one of these, though it's rumored that it's next eruption will be the last one. Ultimately, this is proven to be a hoax.
- Race Against the Clock: Marco and Star have only five minutes before Old Youthful erupts for the last time. Subverted in that the ranger only told them it was the last eruption to mess with them.
- She Is Not My Girlfriend: Marco hastily says this when King River refers to Marco as Star's "boyfriend".
- Shipper on Deck: King River thinks Marco is Star's boyfriend and doesn't exactly disapprove.
- Shout-Out: King River arrives on Earth like the T-800, with (only slightly) more pants.
- Staring Contest: King River has one with a bald eagle, with the intent of breaking its will and taming it.
- Troll: The ranger who tells Marco that Old Youthful is having its last eruption. Turns out he just tells that to tourists for laughs.
- Water-Geyser Volley: King River falls into Old Youthful just as it erupts, sending him flying hundreds of feet in the air. The hot water burns off his hair and makes his skin red and shiny smooth, but he's otherwise unharmed.
- "Well Done, Dad!" Guy: It turns out King River's eccentric behavior and determination to prove himself is because he's worried he and Star are becoming more emotionally distant as she grows up and he grows older.
