Good lord this episode was hard to do. I’m not even going to explain every last little thing we had to do to make it work, but there are a couple of points worth mentioning. First is the eponymous story of the tanuki and Mount Kachi-Kachi (details here on wiki). The summary is that kachikachi-yama isn’t a real place, it’s the sound of crackling wood on fire. This is also where the boat of mud comes from, and how it melts in the water.
Second is the relation between tanuki, sometimes called raccoon dogs in English, and their etymology. Something I only learned through research for this script was that actual raccoons, called literally “washing bears” in Japanese and several other languages, probably got that name from the original taxonomist Carl Linnaeus, who named them Ursus lotor for “washing bear”. It was only later when raccoons were separated into their own genus. The point of all this is for a joke that tanuki can be mistaken for raccoons, which are called bears in Japanese.
And finally, the more astute of you will notice that Trigger screwed up left and right field positions. A native English speaker would never do this due to the commonality of the phrase “out in left field” meaning in the middle of nowhere, but whoever wrote the line was confused.