"We set a goal when we were 10 and 12 to play at Wacken before we reached our 20s," guitarist and lead singer Lewis said.
"We would watch YouTube videos of these giant crowds stretching to the horizon, just moshing hard out and doing enormous circle pits and go, 'Yeah, that's what we want to be doing.' I know it's just the beginning, but being invited to play at Wacken Open Air feels like we're making it as a metal band."
While the band has known about the gig since September, the official announcement was only made around midnight NZ time on Wednesday via the 'Advent Calendar' on the Wacken Open Air website, which has been announcing 2 or 3 bands a day since December 1.
"It's funny because most people were counting down to Christmas," bass player, Ethan Trembath said.
"But we have been counting down to the day we can tell people we're on the bill at Wacken."
Nicknamed 'The Holy Land' by metal fans, Wacken Open Air attracts metal fans from all over the world, with all 75,000 tickets typically selling out less than 24 hours after they go on sale, before the lineup is even announced.
Headliners for the 2018 festival include Brazilian metal giants Sepultura and 'Godfathers of British Metal' Judas Priest.
"We are often compared with Sepultura [who sing in Portuguese as well as English] because quite a lot of our songs are in te reo Maori," drummer Henry said.
"So it will be cool to play at Wacken with them and hopefully meet them."
The band is also hoping to meet Judas Priest, either at Wacken or Metaldays in Slovenia, where both Judas Priest and Alien Weaponry are also performing.
"We saw Judas Priest at Westfest in Auckland three years ago and they were amazing," Ethan said.
"It's still hard to believe we will actually be playing the same festivals as them next year."
Rob Halford, lead singer for Judas Priest, has said of Wacken Open Air, "Wacken is one of the most important festivals in the world … [it is] a home [for metalheads], a special vibe, strong and powerful."
The teenagers had the problem of getting there - until Creative New Zealand came on board, approving a grant of $19,000 to cover travel, insurance and transporting instruments.
"We were all still at school this year, and there's no way we could have raised that much money ourselves," Ethan said.
"So we are incredibly grateful to Creative New Zealand for helping us."
The news has already got Kiwi metal fans excited, with 'The Axeman' Paul Martin saying it's "Quite possibly the biggest news in NZ metal, ever", on his Axe Attack Facebook page.
