In the '80s -- when metal was most commercially and critically acceptable -- the bubbling "underground" was what kept the genre interesting. While major labels were releasing dozens of excellent metal albums every month, the joy of exploring the output of tiny labels always seemed more rewarding, because it was those labels that put out the darker, the heavier, the more diabolical-sounding recordings. And that was what defined the metal underground then: darker, heavier, more diabolical. Never were there metal albums that were weird. That just wasn't part of the game plan when it came to such a direct, visceral genre. Twenty years later, the scenario is somewhat different. While metal has become acceptable to the mainstream again, the metal underground is exponentially more experimental than it's ever been in the past. Blame it on Mike Patton, but a musical form previously castigated as the sole purview of moronic jarheads has positioned itself as the only forward-looking aspect of pop music. Exhibit A: "Way of the Dead" by Chicago jazz-metal outfit Yakuza. Yes, "jazz-metal. Profoundly inspired by their hometown's genre-less improv scene, Yakuza forcefully merges the traditional thudding histrionics of metal with a resolute sense of musical exploration that owes more than a substantial debt to freeform jazz's skronking liberty. It all comes together quite well on the first seven tracks of "Way of the Dead," during which the quartet stomps on quick-change tempo shifts and squealing, post-hardcore violence. It's heavy on the metal, with unmistakable flourishes of out-there intelligence. It's unlike any heavy-rock record you've ever heard. Yet, if those seven tracks lend a certain expectation to Yakuza's sound, such preconceptions are roundly dashed by the final cut on the disc, the 43-minute (!) "01000011110011." Spacious, free and completely unheavy, the piece is thick with avant-garde atmosphere and muted freak-outs by each member of the group. It's absolutely stunning in its incongruity. And for that, Yakuza should be roundly praised.