Diablo 4: The Festering Dark Walkthrough and Map

The Festering Dark is a new Stronghold introduced in the Vessel of Hatred expansion. Found at the southernmost part of Nahantu, it requires players to use the Reliquary Lantern to illuminate paths, remove barriers, and guide them through to the boss. Prepare for an eerie, tactical adventure in these dark caverns.

The Festering Dark Map

Each Warding Brazier in the stronghold activates a Lantern, which follows a set path, illuminating the area and removing barriers at the end. On the map:

Colored circles correspond to Warding Braziers.

Arrows show the Lantern's path.

Colored lines indicate barriers removed by the Lantern.

There are two extra levels to explore:

Skittering Darkness

Vile Darkness

Each level has two entrances/exits, located at either end.

The Festering Dark Location

The Stronghold is situated to the south of Nahantu. Approach from the east until you see the stronghold icon on the map. You'll find a path leading underground at the cave's entrance.

Walkthrough

Entering the Stronghold

Descend the cliff and enter the cave's mouth.

Interact with the necromancer's corpse to pick up the Reliquary Lantern. This item is essential for exploring the stronghold.

While holding the Lantern, you can only use Rathma's Ire, an AoE Shadow Damage ability that drops the Lantern upon casting.

Runes of Trag'Oul scattered throughout the area allow you to resummon the Lantern if lost.

Move north to the first black tendril barrier and use the Lantern to dissolve it. Climb the cliff to continue.

Lighting the Warding Braziers

Locate the first Warding Brazier and place the Lantern in it.

Follow the light as it travels west, removing a barrier and dropping the Lantern.

Pick up the Lantern and proceed to the next area, descending into the Skittering Darkness.

Skittering Darkness

Follow the curved corridor, dropping the Lantern as needed to eliminate mobs.

Head west, then take either of the two northwestern paths (both converge).

At the end of the hall, turn east and return to the Forgotten Depths.

Tip: Unactivated Warding Braziers appear as white circles on your minimap. Once activated, they turn grey.

Routes to the Boss

Bottom Brazier Route

Light the bottom Brazier and follow its path east to remove a barrier.

In the next room, light another Brazier to follow a long, looping path south, north, and southeast, removing another barrier.

Head north through the cleared barrier. Climb up the cliff, defeat enemies, then descend west into a room with three Braziers:

The left Brazier leads to a dead end.

The northwest Brazier loops back.

Light the northeast Brazier and proceed to the final room.

In the final room:

Light the top Brazier for a direct route to the boss.

For more mobs and elites, light the south Brazier, which loops counterclockwise and converges on the same path.

Top Brazier Route

Light the top Brazier and follow it east-northeast to remove a barrier.

Head south past a black barrier, then curve east into the Vile Darkness.

Traverse the tunnels, defeating mobs as you go. Cross a rope bridge and light the Warding Brazier at the other end.

Continue east, lighting Braziers to clear barriers. Both routes eventually converge on the path to the boss.

The Festering Dark Stronghold Boss

Maleficium

The boss fight takes place in a circular chamber with a central Warding Brazier. To summon Maleficium, light the Brazier. Additional Braziers appear at the north, south, east, and west of the room.

Mechanics

Damage Phase: Maleficium can only be damaged while standing in the illuminated area of a lit Brazier.

Brazier Extinguishing: Maleficium periodically links to and extinguishes Braziers, requiring you to relight them.

Half-Health Phase: At 50% health, Maleficium releases a dark energy wave that extinguishes all Braziers. Use the Lantern to reignite them.

Attacks

Ghostly Creatures: Summons entities that form a grid of blood-red lines. Avoid these to stay safe.

Red AoE Pools: Summons damaging pools that may block access to unlit Braziers.

Red Clone: Creates a clone that deals significant damage.

Wandering in Darkness: Deals massive damage when Maleficium is hidden in the dark.

Strategy

Stay mobile and prioritize relighting Braziers.

Dodge melee slam attacks and AoE pools.

Focus on dealing damage while Maleficium is in illuminated areas.

Post-Battle

After defeating Maleficium:

Climb the stairs to the north.

Activate the Wanderer's Shrine to unlock the Gates of the Necropolis waypoint.

If you're looking for guidance on acquiring Diablo 4 gold and items focus on dungeons with dense mob populations like Ruins of Eridu or Champion's Demise for consistent gold drops. Focus on upgrading high-stat Diablo 4 items rather than spreading upgrades across multiple pieces.