The best art is one part imagination and 150 parts perspiration. So when we heard about the Richmond Art Center asking Oakland installation artist Erik Groff to quickly whip up something interesting, and how he worked for three weeks straight until the pale human termite had erected a twenty-foot-tall shantytown cityscape replete with interactive caves -- we said "Kickass!" Then Groff did a similar number on the LoBot Gallery with St. Peter's Church and Bones, a seventy-square-foot shanty church built from Oakland debris and Groff's a priori sense of construction. Visitors literally left the installation on their knees. "I've just gone psycho with the architecture, or anti-architecture thing," the 29-year-old former painter says. Good thing. Groff takes an arresting, original sense of form and color and welds it to a refugee's sense of zoning. The painstaking result is comic, complicated, and gleefully one-of-a-kind. One in five people in the world live in urban slums and shanties, and their numbers will double in our lifetime. The East Bay's most visionary artist sees that future and gets back to work.