Kamikaze is a great alternate finish to B12. Follow the description for B12, going right at the described branch point onto Kamikaze. This trail offers more steep, speed-control riding down to the Municipal Campground where you can then take the Rotary Trail along the river back into town for a beer.
Kamikaze could also be ridden as a short loop combined with the end of B12. Ride up B12 from the Rotary Trails above the high school. When you reach the aforementioned branch point of B12 and Kamikaze, head down onto Kamikaze to the campground.