#A9: Math Path

 When I first saw the name, I quarter-expected it to have something to do with Equation Paths. I ended up learning the rules through rule deduction on the original 4 puzzles' thumbnails. The ruleset has a nice balance to it, and I thoroughly respect the ability to have regions without marked operations, although a thermometer variant might help in small spaces.

The rules have been adapted slightly for this set:

Place a number between 1 and 16 into each cell so that consecutive numbers are connected through kings' moves. Numbered regions require the numbers in that region to either sum, multiply, subtract, or divide into that number, with numbers being processed in descending order for subtraction and division.

This themed pair took a while to make and was themed off an unreleased binary Ken-Ken.

The appearance of 1 2 9 was entirely accidental.

I hope you'll forgive me for not wanting to construct a 12x9 puzzle in this genre.