Māori metal band Alien Weaponry recently played the Copenhell festival and brought a little of their culture along with them. The band made the entire crowd do the ceremonial haka dance, which you might recognize from New Zealand sports teams or even from videos of schools from the country.
I'll let Wikipedia explain exactly what the dance is, as not to get it wrong.
The haka is a ceremonial dance or challenge in Māori culture. It is a posture dance performed by a group, with vigorous movements and stamping of the feet with rhythmically shouted accompaniment. Although commonly associated with the traditional battle preparations of male warriors, haka have long been performed by both men and women, and several varieties of the dance fulfil social functions within Māori culture. Haka are performed to welcome distinguished guests, or to acknowledge great achievements, occasions or funerals.
According to Copenhell, the haka was performed by over 6,000 people at the show.