This awesome route shares the same starts with Grendel and Tinkerbell's Nightmare. Start at the second line of bolts from the uphill side of the tower (where the loose under-cling is). Climb to the ledge and continue straight upwards, and branch left where the route meets with Tinkerbell's nightmare.
There is a sequency crux 3/4 of the way up, hang on til you clip the anchors!
Location
Shares the first bolts with Technowitch then heads straight up. Second climb from the left.
Maybe not the best 12 on The Tower but I think it is the best route of the three 12's on the left side of that face. It's a little harder than Technowitch and Tinkerbell's Nightmare but has more vertical feet of good climbing than the other two so you get more bang for your effort.