I was reading Stuart Anslow's Encyclopedia of Taekwon-do Patterns, Vol 2, and he also covers the GTF forms in the book. One of these is Jook Am, a hyung created by Grand Master Park, Jung Tae. This appears to be one of the longest and most difficult forms to perform to me. Lots of slow consecutive kicks, and then fast consecutive kicks, jumping kicks, especially the flying 3-directional kick.

I didn't know if many of the Korean stylists here had seen or heard of it, and thought I'd throw it up here. Looks like it would be fun, but a bit out of my talent zone to perform well:

I have seen it before (but never in person). Seems to me to be a lot of bits there from the other ITF patterns; bits of Yon-Gae and Moon-Moo with a bit of Juche thrown.

I'm not overly enamored with it - mainly because it's so long! (Does Anslow's book say how many moves there are?) It definitely looks challenging to learn and perform and would be great for working on your kicks. But having said that, I can't really see a need for it if you already do the Chang Hon set. Most of the moves and combinations seem to be covered in other patterns.

95 moves. Loooong!