A 1-4 High or Horns setup has a lot of different options on how to attack the defense. Plays can use the Horns as a double screen. Plays can use different cuts such as Iverson cuts or smash cuts to start plays. Another way to use the horns setup is by having the entry pass go straight to one of the post players and let them operate at the high post area. A lot of teams in NBA are using the post at the high post to run the offense. Jokic in Denver is a good example of this.
This is a play that has everybody working around the ball in the high post. Plays can be complex or simple. They can be worked for an inside shot or outside shot. There are many different options teams have when using a post player running the offense in the high post area. In this play every other player is working around the ball and letting the post player make decisions on where and how to attack the defense.

Option #1
The play starts with the entry going into the center(5). On the catch, the guard(2) cuts to the basket looking for a backdoor pass and layup. While this option does not work often, it does get a basket every once in a while. A good hard cut can get the offense an easy 2 points. If the backdoor is not open, then the play moves into the 2nd movement.

If the backdoor cut is not there, then the point(1) is cutting to the ballside wing to get the ball back off of a handoff. This puts the ball on the wing back in the hands of the point(1). The guard(2) is continuing across the lane to the backside block. The forward(3) is coming into the backside elbow next to the big(4).

Option #2
After the handoff the center(5) is diving down to the block for a possible post feed. The backside action will take away all of the backside help leaving the center(5) all alone against just their defender.
Option #3
If the backside help still rotates over to the center(5) then the guard(2) is coming up the lane using the double screen by the forward(3) and big(4) to the top of the key. When the defense commits to helping on the center(5) then the guard(2) should be open for a catch and shoot at the top of the key.
Conclusion
This is a good play to use in addition to more traditional horns plays because it can change the normal routine of this initial setup. If the defense starts to overplay things because the offense is doing the same actions then a curveball needs to be shown to get the defense back off balance.
This play also forces a post defender to have to guard the ball away from the basket. A bigger and slower post defender can be put into big guarding positions by making them defend away from the basket. A high post entry into an offensive set can present a lot of problems for a defense. By making defenders guard in ways they are not accustomed too, the offense can force the defense into giving easy baskets.