Generally, you should include:
Rahyeh, the Black Sun, was very close to death and had 15+ bleed stacks on him. He was getting ready to take off for the void strafe run attack or something like that, and he died during the interface between those two phases.
I got two piles of loot, one in the middle of the arena and one down at the southern most edge, and heard him say his last dying words twice, a second or two apart from each other.
I suspect it has something to do with the DOTs and phase transitioning. Oddly, the second pile of loot did not include a boss-specific unique but had a Last Laugh Imperial Warsword.
I have farmed Rahyeh for Eternal Eclipse on another character, and never seen anything like this after maybe 10 kills.
Thanks!