To be honest I think you guys are shooting in a wrong direction.
If you want to intimidate an ENTJ it is unlikely that you will intimidate him/her by harsh language , threats , physical violence , scary scenes/pictures etc.
However more subtle things might work.
Here are some examples
1. If you know how to hit their F side with ease while being quite polite and understanding. So that they can't just yell at you.
The best topics for this are usually something that is related to thier past. (especially if they didn't get quite over it even after so many years.
2. Study their life and past and try to get as many facts as possible. Then try to make a good argument that they are "driving" in a wrong direction for 20 years now. This works especially well in the case where options are limited.
3. They have the weakness of all Es. Which is that they really need people. So if you manage to create a good argument that it is likely that they will be left pretty much alone or even worse complety out of the game that can lead to discomfort from their side.
If you want to intimidate an ENTJ you will have to do through logic since emotional arguments are not likely to work. Or you simply must find a way to their Fi. Since they have a discomfort with the idea that someone can take them with a single "shoot" before they even have the time to react and fight. Or idea that somone can make their strenghts useless or obsolete.
Also just if it is hard too intimdidate them and they are also good in hidding it that does not mean that it is not there.
However if we are talking about stereotypical and/or psychotic ENTJ or ENTJs in ENTJ mode the odds are pretty much zero.