It was a joint effort between Shot First and Carnage Gaming on The Shadowlands server.
Fuzzy got a stream/video recording on it here:
As far as we know it was a world first, but if it isn't we would like to hear otherwise. The strategy is pretty evident in the video, but I'll answer any questions.
The loot was the same as 3+ stacks - 2 dread guard masks and 2 essences - 1 BH piece - also got one BH comm.