In middle of killing, or sometimes even just starting the battle, rahab randomly resets back to full hp and back to phase 1. All bad effects from him like phase 3 no potion curse remains as well. I have faced this bug countless times and finally decided to make a bug report on it.
My last run was going smoothly until phase 3 started and someone in the altar at rahab leaves the map and rahab completely resets, leaving us starting to kill again from phase 1, with no potions allowed.
I cant reproduce the bug at will, but it keeps happening every few runs especially in randoms where people keep randomly leaving.

Sent from my SM-A536E using Tapatalk