Under Control

This is a metapuzzle for the Control Panel round, with these puzzles and answers:

We notice that there are 8 rows of blanks; each row has three purple cells and a question mark. The first three columns have a symbol to denote which puzzle to fill in. The yellow hexagon corresponds with “Pangrams,” the Triforce with “Palace of the Wild,” and the black circle with “Black or White.” As we solve the feeder puzzles these columns are filled with the answers to our feeder puzzles; each feeder answer turns out to be 8 letters long.

Next, we look at the clues for each row. The clues tell us how to find the 4th missing letter, given the first 3. Note that even with only 2 puzzles solved, there is enough information given to narrow down the letters, although it’s harder.

Here is how we solve the first row. We have the letters B, D, and S given from the answers.

Matt: “3 of the 4 letters are in the first half of the alphabet.”

Since B and D are in the first half of the alphabet, but S is not, the missing letter must also be in the first half of the alphabet.

Emma: “These letters are all different letters in my favorite U.S. national park, which is known for its buttes!”

The only U.S. national park with the letters B, D, and S that contains buttes is Badlands. So the missing letter must be A, L, or N since Emma says the letters are all different.

Lucy: “The uppercase missing letter contains a vertical line.”

Using Matt and Emma’s clues together, the missing letter must be A or L. Since Lucy says it has to contain a vertical line, the only possible letter is L.

We solve all 8 rows like this (see Appendix), and get the answer LUCYLIES. Submitting this tells us to keep going!

It turns out that Lucy is lying, and we must re-solve all 8 of the rows using the opposite of what Lucy says. For example, in the first row, now the letter must not contain a vertical line. So the only possible letter is A.

Re-solving the rows gives us the final answer, A DEAD END.

Appendix

Authors' Notes

When writing the Control Panel round, we wanted puzzles to have complete freedom on their answers. This meta was written after the puzzles. It was a complete coincidence that each puzzle chose an answer that was 8 letters long.