The year was 1989. Slayer, had experienced their big breakthrough three years earlier with the genre-defining Reign in Blood and were one year removed from their pivotal South of Heaven record, were leading the charge for extremity in heavy metal. Meanwhile, a young Pantera, who had just recruited Philip Anselmo, were at a crossroads, looking to finally catch their break after failing to secure a record contract on the back of their glam metal pandering. Many credit Anselmo's adoration of Slayer as the catalyst for Pantera finding their signature sound and perhaps Pantera's Dallas, Texas jam session with Kerry King marked the point of no return.

The video above is loaded with two hours of footage, most of which shows Pantera and King running through an assortment of songs from Pantera, Slayer and Judas Priest. At first, King and Dimebag Darrell work out some riffs together and by the end of the footage, the Slayer axeman performs four full songs onstage with Pantera.

Check below for timestamps to various parts of the video.

WITH KERRY KING:
Dimebag & Kerry King Jam @ 0:00
"South of Heaven" (Rehearsal) @ 10:57
"Raining Blood" (Rehearsal) @ 24:55
"Power Metal" (Rehearsal) @ 34:56
"Deathtrap" (Rehearsal) @ 44:30
"Green Manalishi" (Rehearsal) @ 48:43
"Metal Gods" (Rehearsal) @ 54:04
"Hell Bent for Leather" (Rehearsal) @ 58:03

BACKSTAGE: @ 1:05:54
Intro ("Shattered" demo) @ 1:07:56
"Over and Out" @ 1:09:13
"Psycho Holiday" @ 1:15:06
"Heresy" @ 1:21:12
"We'll Meet Again" @ 1:27:21
"Domination" @ 1:33:11

WITH KERRY KING:
"Raining Blood" @ 1:41:14
"South of Heaven" @ 1:43:42
"Power Metal" @ 1:47:56
"Metal Gods" @ 1:53:35

In 2014, Anselmo spoke about the weekend jam on the Talking Metal podcast. When asked what King was just jamming for fun or with more serious intentions, the singer was hesitant to answer. “Ooo… I shouldn’t probably talk about this but … I do think… I’ll put it like this, he was having fun. I don’t think he was trying to help us as much as have fun himself and jamming with Dimebag because I know Dimebag blew his mind as a guitar player and really," said Anselmo. "He loved… I guess his love of Judas Priest and where my vocal range was at the time. He loved it and I think it was a nice departure for him to come down and jam with us so I’ll just say he’s having fun but… I could say more but I won’t.”

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