This technique is divided into front and side downward strikes. The
knife hand and back fist are the main tools, though occasionally the
side fist and back hand are used. In both cases the attacking tool
becomes level with the shoulders at the moment of impact. Keep
the arm straight when using the knife hand or the side fist while
slightly bending it for the back hand or the back fist at the moment
of impact.

Side Downward Strike (Yop Naeryo taerigi)
The attacking tool reaches the target in a circular motion and can
be executed nearly from all stances, though L-, rear foot. vertical
and X-stances are most suitable. Keep the forearms crossed in
front of the chest with both back fists faced upward, placing the
striking one under the other at the start of blocking. All downward
strikes are considered side downward strikes unless special
directions are given.

Front Downward Strike (Ap Naeryo Taerigi)
The attacking tool reaches the target in a straight line and is chiefly
executed from walking and X-stances, though sitting, parallel, close
or one leg stance is frequently employed. The knife hand and side
fist are mainly used, though occasionally the back fist, back hand or
base of knife hand can be used.
Downward strike
(Naeryo Taerigi)