Alien Weaponry have already toured nationally and supported some of the biggest names in New Zealand heavy metal.
Ethan thought the stand-out factor for the judges was the Maori element in their performance.
"Incorporating haka and te reo into metal is not common but it works really well," he said. "It's a high-energy stage show - Lewis was leaping around and it all must have helped to wow the judges."
Alien Weaponry also won the Smokefree Pacifica Beats Award on Friday.
The Monkey Assassins - Shane Richards on rhythm guitar and vocals and Buster Clark on drums - from Rodney College placed second.
The two bands win musical gear from the Rockshop and their suppliers, and now have to submit 15 minutes of their best material for selection as national finalists.
The top two solo-duos from Northland from the regional heats last week - Izaia Tilialo from Kamo High School and Huia Shortland from Te Kapehu Whetu, and Guy Yarrall from Kerikeri High School - have made it to the national finals.
Founder and director Glenn Common said the Northland finalists would have to work hard to make the most of the opportunity offered by Smokefree Rockquest.
"They have to submit video footage of their original music that will be judged in August as we lead up to the national final," he said.