Horn's Mother is the overhanging, leaning, off-fist crack to the right of Edward's Crack on the Coke Bottle, of Walt's Wall. It is shaded in the Walt's Wall photo, attached.
The route is a must for lover's of off-width, but it will abuse the wide-crack virgins. The two guys that followed me loved it, but they lost both Pride and blood on the route. From the first belay, one can walk two #4 Camalots up the crack for 40' or so with an occasional rest until the crack begins to taper down. Be prepared to overheat on the strenuous climb. People with small hands may find the climb hard at its grade. People with large hands might find it easier.
Protection
The crux is 10-15 feet from the ground pulling out of a small roof/overhang a few moves above a 3-4" cam. 25-30' up there is a fixed belay. From there, the pro goes to #4 Camalots for 40 feet, until the crack begins to taper down, gradually narrowing to 2 inches at the top. Fixed anchors are at the top and a 70m rope will get you down with minimal effort. A single 50m can be used if you make 2 rappels onto Walt's Wall.
What? Who designed this page, Horns is on the Coke Bottle not Walt's wall. Minor detail I know, but with a decent guide book around, at least the route locations should be correct. It is however a great route.
I also walked a couple large cams up what would be the second pitch. This created some problems for my second. In a fall, he would have swung left onto Walt's Wall with no possible way to get back on route. I pity the foo' who has to lower, and climb that nasty crux again.
"but lost both Pride and blood on the route" - I resemble that comment. This route is very sustained and requires a tremendous outlay of energy. The first short pitch may be a bit of a sandbag, but I'm a relative fist crack newb.
I would agree that this is a possible sandbag (unless you have huge hands like Bob S.). At the crux I had to shove my whole arm in the crack to get a fist jam, but was only able to get one arm in at a time which made upward progress a little problematic.
Unless I'm retarded (entirely possible) I don't think there are any fixed anchors on top of this climb, only on top of 4th of July. I built an anchor with #1 Camalots, but anything hand-sized would work. I would also bring more than 2 #4 Camalots if you don't want to be bumping them the whole way.
I didn't see a fixed anchor either and used #1 cams and #3 cams to build one. I would also add that rapping from the chains atop 4th July crack with a 70 meter rope won't get you down with minimal effort. However, if you go to the ends of your rope, you should be at a small ledge partway up walt's wall, and an easy down climb will get you to the dirt.