Here's what happened
So, we're running through the bosses to clear so we can get LK down (actually did it too - day after this little event) and come across Bloodqueen. We set up our usual bite order, no biggie, we pull and we're off to the races.
So we're about a minute and half into the fight, our RL is calling normal stuff, and all of a sudden over vent we hear "is anyone bitten yet?" - LOL. The bite bugged out - or something (we figured it out later) - with the mage that got the first one (it was the iceblock that did it) and at the point where 4 of us should have had the bite, no one did.
So a couple of us check the enrage timer vs BQL health, and we figured it might actually work. So we down her with no bites, and the entire raid gets Once Bitten. She was about 1.5 seconds into her enrage when she died.
We figure it should be an achievement or something.
(oh, I also f***ed-up heroism, so we lost about half of it to her floating phase)
Here's how to reproduce it
Make sure the first person who gets bit (and if you don't know how to guarantee who gets it first, you are not ready for this ) can do some form of purge or suicide. For us, while we discovered it by accident, we figured out it was the mage iceblock that caused the anomoly, and we can repeat it now (not that we need to - lol).
Have fun!