The Flake is a seldom led classic, and a good test piece for those who are up for it. Be warned it is a significant step up in terms of difficulty and commitment from the Watusi and Shotgun, both of which are safe but spicy 12's. Note the Todd Swain Arizona guidebook misrepresents the path of this route and Bach's Celebration in the photo.

Begin a few corner systems to the right of Paradise Lost, just right of the "I am the master" graffiti (I recommend reciting this mantra before leaving the ground). Climb up relatively easy but exfoliating rock to a stance below a roof. Under this roof are some suspect wedged blocks - apparently on the FA the huge namesake flake was trundled here - but with care you only need to yard on the most solid of these. Bust a frightening and committing move left around the corner to a sloping stance. This is where Bach's Celebration continues straight up and The Flake moves back right. Much good gear can be arranged here, including a pretty solid #3 Camalot at the top of a flaring crack. That's it for awhile. From the sloping stance reach right and bear hug up twin aretes until it is possible to rock over to the right to another stance. Scary moves lead up to a decent incut where you may be able to place tiny pro overhead. If solid, the crux, a desperate, powerful, and balancey affair, is reasonably well-protected, but if this gear fails, you're in for a long, violent ride. The crux culminates with better holds and gear. Finally, pull up onto a ledge at the base of a final stembox. This section is also cruxy and requires thinking inside the box. The pro is good, but only an attentive belay will keep you from plopping back onto that little ledge.

Whew! This route is really good and will expose your mental and technical weaknesses. It could easily command 12+ and have several bolts at many lesser areas. 

I enjoyed having HB offsets, BD Micro Stoppers, a random Metolius Astro Nut, a 00 TCU and a #3 Camalot... and an assortment of wires and cams in between.