Because the wall is static I would add the vertices at that end of the rope to the choreographed group.  As long as you dont move the rope prop itself, those vertices will remain absolutelt static as if welded to the wall.  It works a bit like adding a pin.

That method doesn't rely on the wall being a prop or a figure at all, it doesn't have to be part of the simulation at all.

For the horse end, you shouldnt have to parent it to the horse, as long as the horse is a collision object you should be able to add a few vertices on the end to the constrained group.  Though I think that you may need the end to be quite close to or touching the horse itself.

I hope that helps :)

Fugazi (without the aid of a safety net)

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