Beth'tilac retreats to the top of her web at the beginning of the encounter.
Beth'tilac slowly loses Fire Energy over time. Cinderweb Drones also siphon some of her energy when their own energy is depleted. Whenever Beth'tilac runs out of Fire Energy, she will set herself ablaze, causing Smoldering Devastation.
After she has performed Smoldering Devastation three times, Beth'tilac enters a frenzy. She lowers herself from the safety of the top of her Cinderweb and no longer calls for aid from her brood.
Lord Rhyolith ignores players while his armor is intact, but they can attack his feet to control his movement.