Ballad of the Baphomet iv

maturutuki

Baphomet can throw player off the map. In the effect player stumbles in the invisible wall and cannot damage boss.

plasticbat

It has been like that for a long time. To avoid that, keep staying between Baphomet and the center of the arena.
By the way, AOE attack can still damage the boss when you are outside. Your pet can still damage the boss.
I killed the boss few times when I was outside the wall but it was before mod 16.
Probably, it was not Baphomet did that but Minsc or Knox.
Sometime, you could be knocked back in too.