People who downloaded the Moria set will notice all of the Moria rocks are in the Minas Tirith Citadel tab, but now are colorable. You'll also notice the mountain pieces from the Harry Potter set are included as well, also colorable. I needed to create the white/grey rock of Minas Tirith and didn't want to make extra pieces, so just repurposed what I already had.
So the pinnacle can be created by stacking the angled rock pieces. Topping off the pinnacle with the courtyard takes a little work, and a trick.
The lettered pieces are the ones that will be used:

While A and B look similar, they have to be used opposite one another or the edge of the courtyard railing won't line up (as seen in the foreground of the assembly picture below). So use B in the foreground and A on the back side. If you use B in the background, it'll look ok when viewed from the front, but when you rotate the board it'll look offset (as A does in the foreground above).
I'm sure it's an alignment glitch I could have fixed, but would have required me to completely rebuild pieces D-I so I made 2 1x1 pieces to accomodate the "glitch" instead. Lazy, I know, but a lot less work.
Piece C can be used anywhere you have a 1x1 tile where rock meets brick. It has 4 unique sides so you can rotate it for variety. D & G are to be used at the end of the pinnacle. The set was built to have at least 1 tile of path between them, but you can use more if you want. Also note that the path drops 1 level (steps down) toward the tip of the pinnacle.

Stack colorable rock 1x1 tiles below C (as in the back of the pinnacle) and stack blank brick tiles on top of C (as seen at point of pinnacle) to finish the effect.