Embusen
The "embusen" line varies for each series of "kata". It is, for example, a straight line for the Shōtōkan "Tekki" series of "kata". It follows the form of a capital letter "I" for the "Heian" series of "kata", as well as for the "Taikyoku" series. More advanced "kata", such as Shotokan's "Kanku-Dai" and "Gojūshiho Dai and Sho kata", as well as the Gōjū-ryū "Seipai and Kururumfa kata", for example, have increasingly more complex "embusen" to train the practitioner in more advanced defensive angles and footwork. For any "kata", the "embusen" is fixed and must be followed  exactly for proper mastery of the style. The rule of embusen. Japanese Kata are mostly arranged to start and end on or around the same point. Many were modified from their original Okinawan versions to accomplish this feat. The purpose of this is simply to allow the movements to be practiced in a small training space. The rule of embusen is that any movements in one direction should be symmetrical and countered by an equivalent number of movements in the opposite direction. In Okinawan karate the maximum number of steps in any direction is normally three.