Moon Moo
Moon Moo is one of the final 4 of the original Chang Hon patterns. Like the other later patterns, it contains much less Karate influence when compared with the earliest. Moon Moo is exceptional, though, in its almost excessive emphasis on leg techniques and incredibly difficult kicking, most likely with the intent of distinguishing it from Karate as much as possible. Because of this, there is little to discuss in Moon Moo.
Admittedly, Moon Moo is not a pattern that I have yet learned, and I could very well be missing things. With all of this considered, the following is all that I have been able to find.
The following videos were used as reference:
ITF Legacy performance of Moon Moo.
Kim Suk Jun performing Moon Moo.
Hirokazu Kanazawa performing Enpi (Shotokan).
Moon Moo is one of the most unique patterns I have ever seen. The kicking, again, is unheard of in Karate kata. This low punch in the X stance, however, is found repeatedly in Enpi.
The bending knee stance into the back kick is recycled from Ko Dang, and Moon Moo also reuses the stepping pressing blocks from Choi Yong (originally Unsu).
I'd like to point out how the rhythm of this section differs in the videos above. The Legacy video comes to a complete stop on each step, while Suk Jun Kim walks though them in a manner closer to Choi Yong and Unsu.