There are many variations of the hook kick, generally based on different foot work: rear- or front-leg, oblique or half-pivot, dropping, spin-back and more. The hook kick can be delivered with a near-straight leg at impact, or with a hooked finish (Kake in Japanese Karate) where the leg bends before impact to catch the target from behind. An important variation is the downward hook kick, delivered as a regular or a spin-back kick, in which the end of the trajectory is diagonally downwards for a surprise effect or following an evading opponent. Another important variation is the whip kick, which strikes with the flat of the foot instead of heel.