Tamed Elegon boss on my hunter after learning the cloud serpent tome. I was left stuck in his room and had to hearth out. I went back inside to finish up Mogu’shan Vaults, but was unable to progress due to the encounter never resetting. Trying to do a soft reset didn’t work, either.
May be able to get around the issue by using another person’s lockout, but I did not have the time to test this out myself.
Edit: TIL Elegon is categorized as a spirit beast, not a cloud serpent.
I am having the same issue , tamed Elegon , got stuck inside the room, hearthed out , soft reset , flew back to the raid , boss encounter still active even though my lockout says he has not been killed ( was not killed , was tamed ) , I cannot finish the raid because elegon is still active.
Uh, I don’t have the “cloud serpent tome” learned, however I was able to tame Elegon twice… where is this tome?
btw, I tamed him yesterday hearthed out, and then tamed him again today
This bug is so annoying I wanted to tame Elegon a 2nd time but when I went back same exact thing, cant continue the raid even though it shows Elegon is alive… Tried using another person’s lockout but get the message that I am locked to my raid that is broken. Guess we have to wait till Tuesday.
It’s sold by the quartermaster at The Arboretum in the Jade Forest.
thank you, kinda funny tho, I didn’t need the tome to tame Elegon
That’s because Elegon is a spirit beast, not a serpent like the cloud serpents.
Ah that’s why, thank you
Just do what I did, que for the legacy LFR and it will let you tame it for the 2nd time
TIL. Thanks! 
Just tamed him on mythic, and went afk for a min, came back and he respawned so I was able to tame a second one. Then respawned again and was able to kill to progress the dungeon.