I had an email from an Ancient Frog player, frustrated that he couldn't reach par on the 'easy' puzzle 15.

Difficulty ratings are an inexact science in Ancient Frog - in many cases, a puzzle will switch from frustratingly hard to really trivial just by changing one move. I try to rate them so that puzzles requiring twisty turny routes are marked harder than ones which are mostly solved in a straight line. Overall, the difficulty levels average out to about right, but sometimes they just don't reflect what a particular player is experiencing,

Anyway, I sent him the solution, at least in part to show that the par rating was achievable. It was a bit of a faff describing the route (using ascii art), so I decided to write a little tool to generate solution slideshows.

Here's the output for puzzle 15. (look away if you don't want to know the results!)