[niffer]

^

You see, that's ENTJ humour. More direct.

An ENTP would play along for a longer time..

It's kind of hard to describe the difference, actually, now that I think about it. P humour in general is just more unplanned and moronic. When a P makes a joke, they do it so that the entire execution of it is amusing to watch. When a J makes a joke, they make it so that if you took a second to think about the mechanics of it, it would be really quirky and/or clever as well as funny.