I use the Gwa Chui as the 2nd major strike and the Chau Chui as the 3rd major strike in SKD 3.0.

The Gwa Chui is a strike using the back of the fist. The PKK Gwa Chui uses a big movement to perform the strike because the objective is to knock the opponent out with a heavy blow to the face that cuts across instead of a backfist that stuns.

The Chau Chui is a diagonal hook that targets the opponent’s body. It is typically a follow up to the Gwa Chui especially when the Gwa Chui is used to clear the way to allow the Gwa Chui to enter.

How to practice the Gwa Chui and Chau Chui :-

1) Stand with feet together
2) Place both hands near to your chin in ready position
3) Take a step diagonally forward to your left. As you do so form a fist with your left hand as you drop it to your chest height. As you step execute the Gwa Chui across from the top right to the bottom left, ending by the side of the left side of your waist. At the same time, as the left Gwa Chui goes out past the left side of your face, lower your right fist to the right side of your waist in preparation for the Chau Chui. The moment the Gwa Chui nearly reaches the left side of your waist, quickly let loose the Chau Chui diagonally from your right side to the end at the height of your chest along the right shoulder line
4) Repeat when you step forward diagonally to the right

The power generation relies on how the body is moving and turning. The stance plays an important role here especially the front leg.

The waist can send the Gwa Chui along its smashing trajectory. Use the landing of the front leg to impart additional momentum towards the end of the Gwa Chui trajectory.

At the same time use the dropping and landing of the front foot to “toss” the Chau Chui out. You will feel as if the Gwa Chui is helping to power the Chau Chui.