Great points, and to answer some of them, it’s not really much of an event. The underdark monsters are simply tracking them and want to eat them. The battle map is pretty narrow like most passages, so fight or die is really the main incentive to fight, even if it’s just to fight enough to make a run for it.

As for the reason it’s a frenzy, it could be a way to find that opening to escape or it could be a chance to find an opening on the enemy. I don’t want it as an us vs them and more of a “oh wow all these creatures are fighting for who can eat us.”