Written & storyboarded by Deena Beck & Angel Lorenzana
The Stump Kids find an base similar to theirs that was abandoned in the 1970s and try to figure out what happened to its previous inhabitants.
Tropes:
- Abandoned Area: The Founders' Keep appears to have been abandoned in a hurry, since the Founders left a lot of stuff behind, including a board game on the verge of being finished. The secret message that Craig deciphers explains that it was left this way on purpose as a message to future generations.
- Always Someone Better: Craig admires the drawings made by one of the Founders, noting that his trees actually look like trees, while his just look like broccoli stalks.
- Cypher Language: The message in the Founders' Keep is written in code. With some help from Duane, Craig is able to decipher it, revealing it to be an explanation for the fort's desertion.
- Foreshadowing: It wouldn't be the first and last time a game of Capture the Flag becomes an all-out war...
- Great Offscreen War: The Founders' message talks about a game of Capture the Flag that went horribly wrong, eventually escalating into an all out war between the different Creek kids.
- Secret Snack Stash: The Founders' Keep has a secret room full of candy. Unfortunately, it collapses when J.P. accidentally pulls out a load-bearing jack-o-lantern.
- Similar Squad: The Founders turn out to be almost exactly like the Stump Trio. One is into space stuff like J.P., another is into comic books just as Kelsey is into fantasy books, and the third is an artist just like Craig, who even made a map of the Creek just as he has.
