Originally Posted by
Choda
For some reason the timing on some events in the fight can affect the outcome of such abilities apparently, partially probably due to latency but also partially due to the way the encounters are coded.
For example, if we went into Cho'gall p2 while the Adherent is spawning, Cho'gall wouldn't despawn it as he usually does, we'd have to wait a few second for the Adherent to become active.
Or, a funnier example, also on Cho'gall, one for which I can't think of an explanation... We start p2, everything is normal, 40s in, a single Blood of the Old God add runs into the raid and starts meleeing people. God knows where it came from.
But yeah, your Atramedes bug is probably just a freak accident, at least I hope so.