The Executioner II (1974)
It's a commonly acknowledged fact that sequels rarely live up to the original... either they try too hard to replicate what made the original good and end up feeling redundant, or they don't seem to have understood why the original was successful in the first place and give us something different - which is rarely what we want when we choose to buy/watch a sequel.
THE EXECUTIONER II definitely succumbs to the latter problem, choosing to sacrifice most of the sex and violence in favour of screwball comedy capers... and it seems to have completely forgotten the fact that Chiba's character is a ninja! There's only two fights in the film, and only the second one of those has any balls to it... and by then it's just too late.
The opening credits for the film seem like they know what we're here for, teasing us with a montage of violence and nudity that the film completely fails to deliver on... much of it was taken from the first film, and almost all the good bits of the 2nd get shown right there... you could stop watching after the credits finish and not miss much at all.
Taken as a slapstick comedy, KARATE INFERNO is fairly decent... though the humour can be a bit hit & miss, and some of the production looks frighteningly cheap - almost as if the intention was to spoof bad 70's films. Taken as EXECUTIONER II the film is very disappointing, though!