Sunday, January 11, 2026

Puzzles 368 - 371: Caves from Mustang Math 2025

I've continued to supply puzzles for the Mustang Math Tournament!  While MMT is primarily a math contest for middle school students (mostly written by high school students), there is one round every year which introduces a pencil puzzle genre.  In previous tournaments, we've covered Fillomino, Double Choco, and Slitherlink.  We give students an overview of the rules, a sample puzzle, and some variants, and ask them to solve as many puzzles as possible.  Some years are harder than others (the Double Choco round in 2023 was particularly nasty...) but we try to make the puzzle set accessible overall, with a few hard puzzles sprinkled in because I can't resist.

Last year, we decided to go for Cave.  We explicitly gave "no checkerboard" as a rule rather than something students needed to figure out for themselves.  Overall, the Cave round seemed to be easier than the Double Choco round from 2023, but harder than the Slitherlink round from 2024, which is not surprising.

I wrote most of the puzzles for the round, with Pranshu (a high school junior at the time) supplying the remaining grids.  Each section had a particularly tricky puzzle at the end, much harder than the rest of the set.  Here are those capstone puzzles; if you want the full set, let me know!