Bug boss syrillax dragon of the north

[Detona]

Hello I would like to report a bug I found in the event boss SYRILLAX IS FLYING AND NOT In this battle to please corigão this bug before it becomes problem in the future and I lost a power = / and friends who were with me

[Madnex]

If he doesn't come back down then yes, it's a bug. If someone leaves or resets boss while he's in the air it happens. What exactly happened?