Now in its fifth year, the New England Metal & Hardcore Festival has grown into a truly cosmopolitan celebration of the metal underground: this weekend at the Palladium in Worcester, Americans Superjoint Ritual and Nevermore join Europeans Opeth and Meshuggah in the headlining slot. The festival has also become a cherished homecoming gig for Boston-bred road warriors Shadows Fall and Converge, both of whom routinely find themselves near the top of the bill. Call it a sign of the underground’s vitality that the festival’s originally announced headliners, Cradle of Filth, were lured away to headline OzzFest’s second stage — even the Osbournes are recognizing the potential of the scene. Including the one right here: after the NEMHF, Shadows Fall will be off to Ozzy’s second stage as well. And they’ll be joined, on both occasions, by Killswitch Engage, the Western Massachusetts metalcore band who have been taking the scene by storm with Alive or Just Breathing, their first album for Roadrunner and second overall.

" This year is going to rule, " enthuses Killswitch guitarist Adam Dutkiewicz. " Usually we all just blow in and out, because we’re not really the big scenester kind of guys. But this year I’m planning on hanging out for the whole weekend, because I’ve got so many friends in bands playing and the line-up is just amazing. I’m also going to do some stage antics. It’s going to involve some rock-and-roll guitar smashing, that’s all I can say. "

Killswitch’s triumphant year almost didn’t happen: at the beginning of last summer, just as they were scoring a cult hit with the stately thrasher " My Last Serenade, " frontman Jesse David Leach left the band. But after canceling a few weeks’ worth of shows, they beat the odds and got right back on the road with new frontman Howard Jones, of the like-minded Connecticut band Blood Has Been Shed.

" I was like, ‘Oh God, there’s no hope’  " Dutkiewicz admits. " I don’t know what’s going to happen, but I’ll try out some people.’ Howard was the one who brought the most to the table. It was like, ‘All right, I think this could work.’ And then once we started playing shows with him, we were like, ‘Wow, this is definitely going to work.’ We lucked out. Who would have thought we would be able to replace a singer in that short amount of time and have people go, ‘Wow, these guys are still good’? "

The band have been on the road ever since: they’re just now taking a break to write their eagerly awaited first album with Jones. After that, they’ll join their old buddies Shadows Fall on the second stage at OzzFest. Hot on the heels of a well-received European tour with labelmates Five Pointe O and 36 Crazyfists, they’re psyched to hit the stage again. " That was such an amazing time in my life on so many levels, " says Dutkiewicz of the European trek. " Every show was sold out, the crowds were really enthusiastic, and it was just amazing to be in all these different countries every day. But we’ll see what happens this summer — maybe things will be topped by OzzFest. "

Killswitch fans don’t have to wait for the new album to hear the recorded debut of Jones with the band: those are his vocals in place of Leach’s on the video for the pummeling new single " Fixation on the Darkness. " Jones also appears on the new Blood Has Been Shed album, which comes out next month on the New Jersey punk label Ferret. And Leach has resurfaced with the remaining members of recently disbanded Boston rockers Medium in a new group called Seemless, who play the Middle East on June 5. Dutkiewicz describes them as " very Kyuss " and gives them a hearty thumbs-up. " I went to see them, and I told Jesse right after they played, ‘Wow, that’s the best you’ve ever sounded, man.’ I think it was definitely meant for him to get out of Killswitch and do something more rock-related. There are no hard feelings whatsoever — we’re still friends and we still hang out. I wish him nothing but the best of luck. "

The New England Metal & Hardcore Festival runs this Friday and Saturday, May 16 and 17, on two stages at the Palladium, 261 Main Street in Worcester. Friday’s line-up includes Opeth, Shadows Fall, Nevermore, Lacuna Coil, Blood Has Been Shed, and DRI; Saturday brings Superjoint Ritual, Suffocation, Lamb of God, Converge, Killswitch Engage, and more. Two-day passes are sold out; remaining single-day tickets are $30. Call (800) 477-6849.