The route identified as "Unknown 5.10a" begins just right of the right-facing corner of "Joke Book" and left of the arete that separates the slabby southeast face from the overhung eastern portion of the Attitude Wall. Begin climbing steep cobbles and aggregate to a horizontal break. Move up and right to the 1st bolt. Climb the slabby face and polished cobbles. Above the 3rd bolt the face becomes thin and forces you right on balancy footholds, but with little in the way of handholds until a large red block can be reached. Continue up along the right edge of the cave on wild pockets to the anchor.