Last year’s King Gizzard & The Wizard Lizard release Demos Vol. 3 & 4 included a hard-rock instrumental called “Converge,” which is set to appear on the band’s forthcoming album PetroDragonic Apocalypse; Or, Dawn Of Eternal Night: An Annihilation Of Planet Earth And The Beginning Of Merciless Damnation. (They recently shared lead single “Gila Monster.”) Sunday night at Boston Calling, King Gizz performed “Converge” live for the first time, and it had evolved quite a bit since the demo. It’s more than twice as long now, and Stu Mackenzie has added lyrics. Seems like a proper heavy metal tune. Watch footage below.