Karl Agell understands the former power of mainstream rock ‘n’ roll. Agell fronted Corrosion of Conformity when the Raleigh band recorded 1991’s Blind. That album fused hardcore muscle to approachable Southern rock, an admixture that pushed COC from the punk underground to package tours with Metallica. After leaving COC, Agell continued the approach with Leadfoot.

But the market has changed immeasurably in the last quarter-century, and rock’s potency on the radio has diminished. The self-titled EP from Agell’s new King Hitter arrives at an interesting time: It has the fortune of being part of a current resurgence in making hard rock, where bands like Red Fang, ASG and Royal Thunder enjoy lives lived on the road and the support of indie labels. But King Hitter has the equal misfortune of arriving at a time when this stuff continues to lose its commercial-airwave market share. Hard rock is now its own reconstituted underground.

With King Hitter, Agell is again at the front of a hard-hitting band. His voice is an agile instrument, able to scorch and seethe. His melodic leads suit broad, evocative lyrics and arena-sized hooks. On “Drones Away,” he wails, “Face to face/We face the truth/Eye for an eye/And a tooth for a tooth.” The political number revels in ambiguity: Are the driving riffs a rally cry for hawkish retribution, or do the minor shades protest war’s endless cycles? As with Blind, there’s a punk instinct here, but more nuanced, impressionistic writing saves King Hitter from simple sloganeering.

“Feel No Pain” captures the new group’s inherent chemistry. Guitarists Scott Little (also once of Leadfoot) and Mike Brown bridge heavy metal purity and Southern rock boogie. They lock steps with the forceful rhythm section of Jon Chambliss and bassist Chuck Manning. Together, the quintet mines the space between Sabbath’s slog and Skynyrd’s speed. During “Suicide is the Retirement Plan,” Agell laments the unyielding grind of unfulfilling jobs. The band, meanwhile, conjures a Southern-industrial metal backdrop, filling the groove between White Zombie and Rise Against.

Not long ago, these songs might have portended amphitheater shows and commercial radio support. But in 2015, as alternative rock radio sheds big guitars for banjos and keyboards, King Hitter’s very good hard-rock start feels promising for an entirely different reason: Karl Agell is working again.