Horadric Strongrooms are special challenge rooms found inside Nightmare Dungeons. These micro-dungeons are short, fast-paced, and full with enemies. They have their own unique mechanics.
Strongrooms are optional, but if your goal is loot, they are absolutely worth your time.
How to Find a Horadric Strongroom
Strongrooms do not appear in every Nightmare Dungeon, but there are ways to increase your chances:
- Play on higher World Tiers. Playing in Torment will increase your chances of finding a Strongroom.
- Use Nightmare Sigils that include an affix guaranteeing a Strongroom in the dungeon.
- Inside a dungeon, watch for a flash of light and distinct sound. That is your clue that a Strongroom gateway is nearby.
Once you find it, defeat the initial ambush of monsters to open the portal and enter the Strongroom.
Inside the Strongroom
Once you are inside, the challenge begins. You will be racing against the clock to earn Horadric Attunement, a score that scales your final reward. You have 100 seconds on the timer to fill up the Attunement bar. Every death will give you a penalty, just like the Pit.
1. Activate Horadric Pillars

You will be given a choice to pick up to 3 Horadric Statues. You can activate more statues if you play at a higher difficulty level.
Statues can either offer bonuses or be corrupted by Astaroth‘s influence, adding risk in exchange for much greater rewards. Choosing the right Pillars can change your entire Strongroom experience: stack buffs, summon tougher enemies, or both.
2. Slay Monsters to Earn Attunement

Each kill gives Attunement. You can see your Attunement score up right, next to the minimap. Completing a Pillar Ritual activates a 10-second buff where all monster kills give +2 bonus Attunement. Use that window to go on a killing spree.

3. Use Sacrifice Shrines

These unique Shrines spawn portals for enemy ambushes at your location. Risky, but use them after clearing Pillar Rituals to trigger the effects faster and gain more attunement.
Strongroom Boss and Rewards

Once time runs out or enough Attunement has been gathered, a boss will spawn. Defeat the boss to complete the Strongroom.

After the fight, open the Grand Horadric Cache. The better your Attunement score, the better the loot. Here are some of the interesting parts of the loot:
Obducite
- Escalation Sigils for Escalating Nightmares
When leaving the Horadric Strongroom, you will receive a buff for the remainder of your Nightmare Dungeon. Here are the possible buffs you can receive:
- Experience: You gain increased Experience from Monster Kills.
- Reputation: You gain increased reputation from Monster Kills.
- Obducite: You gain increased Obducite from Monster Kills in this dungeon.
- Gold: You find 25% more gold.