Underground River Map (Atlas of Worlds)

This map is based on the first part of The Caverns in Act 2. It's a linear series of caverns connected by narrow bridges.

Map Type: Indoors



Boss Arena
An L-shaped cavern at the end of the map. Entrance seals when the boss is engaged.

Boss
It That Fell, based on Q'uru from The Caverns. Repeats the following sequence of maneuvers:
 * Summons a small pack of Plummeting Ursas.
 * Uses and jumps up, disappearing for a few seconds.
 * Lands in the same spot and uses Earthquake again.
 * Enrages for a few seconds.

It's highly recommended to prepare physical damage mitigation, including, in case of being overrun by Plummeting Ursas. It That Fell's melee damage is comparable to one of those Ursas, but it has higher attack speed, especially when enraged. The safest way to deal with this boss is to clear summoned Ursas as soon as possible, wait out the enrage and use the limited time before it uses the Neo maneuver again to deal damage. The pack of Ursas is usually 4-6 strong and there's a danger of being surprised later on by those that didn't drop initially. A good way to avoid that is to walk around the edges of the Earthquake the boss leaves behind when jumping. There seems to be no limit to how many Ursas can be summoned.