Booyagh Piddle is a strange one, since he's scripted to run away and disappear (Literally he just poofs out of existence for no reason) if you try to engage him.
He can sometimes actually enter the fight if you aggro the courtyard and fling spells from up top. But often if you actually engage him first and don't one shot him, he'll just skedaddle.
I don't know why. Since as far as I can tell, he doesn't appear again anywhere else in the game even if he does live (Unlike Fezzerk who'll appear again in Act 2 if you let him live - Either by dialoguing him out of a fight or by beating him so he surrenders)
He just randomly has this strange interaction.
