In big, upper-case letters, the poster says "ILLEGAL," then explains that the man portrayed should be reported — and deported — if he entered the country "without proper authorization." The man is Superman, and people are urged to call a San Francisco number that connects them to a federal office called the U.S. Department of Illegal Superheroes. It's satire. It's highly effective satire. And it's the work of Oakland artist Neil (Clavo) Rivas, who's exhibiting his "illegal superheroes" posters, the logo of his made-up federal agency, and even faux U.S. agents. Rivas, who will attend the event, adopts comic-book characters because, he says, "When we try to speak to someone about immigration issues, it's hard for some folks to be able to relate on any level. But with superheroes, they really care." Rivas' immigrant superheroes include Wolverine, Wonder Woman, Thor, and many others. The logo for his U.S. Department of Illegal Superheroes plays off the logo of the Department of Homeland Security. Art-goers are asked to make a leap of faith into an exhibition that is underlaid with dark, dark humor.